Added the Math Calculators category
A new home for number-system tools, starting with binary. The category page explains how binary, decimal, hexadecimal and octal relate and points you to the right converter for your question.
View pageWhy we publish this
A calculator is only as trustworthy as its upkeep. This log exists so you can see exactly what we have changed and when — including the mistakes we have corrected. Dates here reflect the day the work actually shipped; we do not add entries to make the timeline look busier, and a page that has not changed keeps its original date rather than being re-stamped with today's. For how the tools themselves are built and sourced, see our Methodology.
2026
- Latest
New tool New tool Added the Binary Converter, with binary to decimal and decimal to binary pages
You can now convert between binary, decimal, hexadecimal, octal and any base from 2 to 36 as you type, exactly even for 64-bit numbers and longer, with the place-value expansion or the division by 2 worked step by step. Invalid digits are highlighted, and the page address updates so you can share a conversion.
View pageNew tool Added six binary tools: hex, text, two's complement, IEEE 754, arithmetic and bitwise
The binary tools now cover binary to hex by nibbles, binary to text in UTF-8 or ASCII, two's complement and other signed encodings at 8 to 64 bits, IEEE 754 floats with the exact value stored, binary addition to long division with the working shown, and AND, OR, XOR, NOT and shifts. Each has its own page, and every tool can switch to the others from one set of tabs.
View page New tool Added the Proportion Calculator
You can now solve a/b = c/d for a missing value with the cross-multiplication steps shown, test two ratios or a table of values for proportionality, and work direct and inverse proportion problems such as y ∝ x² or y ∝ 1/x. The same page scales recipes, map distances and image sizes, splits an amount in a ratio to the cent, and keeps answers as exact fractions.
View pageFix Corrected a source link and the cold-patch density hint on two paving calculators
The Tarmac Quantity Calculator's note that mix density, laid-thickness variation and compaction change the tonnage needed now links to Tarmac's own tonnage calculator page, where that statement comes from. The Asphalt Patch Calculator's density hint no longer suggests about 137 lb/ft³ for cold mix; it now says to divide the bag weight by its yield, about 100 to 120 for the cold-patch bags on that page. Its catalog description now says length and width are in feet and depth in inches.
View pageImprovement The nine no-income-tax state paycheck calculators now open at that state's typical wage
The calculators for Alaska, Florida, Nevada, New Hampshire, South Dakota, Tennessee, Texas, Washington and Wyoming used to open at a $75,000 salary. With no state income tax to change the result, seven of them showed the same take-home pay before you typed anything. Each now opens at its state's median annual wage for all occupations (BLS, May 2025), the same figure its worked example uses, and the salary preset button is renamed to match. States that tax wages still open at $75,000.
View pageImprovement Every state paycheck calculator now opens at that state's typical wage
Later the same day, the other 35 calculators, for the states and the District of Columbia that tax wages, also stopped opening at $75,000. At that salary Montana and Oklahoma showed the same take-home pay. Each now opens at its state's median annual wage for all occupations (BLS, May 2025), the salary its worked example uses, so all 44 calculators open on a different figure.
View pageContent Plainer descriptions of the AP, Finance and Tarmac categories
The AP category no longer calls its two calculators a suite, and the Finance and Tarmac category pages no longer describe themselves as professional or precision tools. Each now says what its calculators work out. The District of Columbia paycheck calculator's page title now reads DC, so search results no longer cut it off.
View pageContent Named the person who builds and reviews every calculator
The About page now says who runs OtherCalculators: Shakeel Alvi, a business graduate (MBA in Marketing, with an additional specialization in Management) and full-stack developer with about 20 years of experience, who also runs ConcreteCalculatorMax. The Reviewed by line on each page now names Shakeel instead of an unnamed editorial team and links to that bio, and the Contact page says messages are read by Shakeel, the one person who runs the site. The About page still says plainly that no licensed engineer, CPA or financial advisor signs off on these tools.
View pageContent Rewrote 12 one-line calculator descriptions to say what each tool takes in and gives back
The short blurbs under these calculators on the homepage, the category pages and the calculator list were a single generic sentence such as Calculate AP Biology Exam Score. Each now lists the inputs the tool asks for and the results it returns, checked against the calculator itself: the asphalt repair, milling, road and patch tools, aircraft finance, 401(k) contribution, Solo 401(k), tree removal, ERA, AP Biology, AP Chemistry and tarmac quantity. The calculators themselves did not change.
View pageContent Gave the AP Biology and AP Chemistry calculators their own exam details
Each page now sticks to its own exam and adds details from the College Board's published format: the skills the multiple-choice and free-response sections test, the calculator policy, and a worked example built on that exam's own free-response questions. Text the two pages used to share, such as the pitfalls list and most of the FAQ, was removed or rewritten for each subject. The explanation of how an AP composite becomes a 1 to 5 score, and what a 3 means for college credit, now appears once on the AP calculators page, which also uses the College Board's own score labels and no longer says the estimates are the most accurate possible.
View pageContent Gave seven asphalt and tarmac calculators sourced figures for the one job each does
The asphalt patch page now compares cold-patch coverage from QUIKRETE, SealMaster and Unique UPM (about 5 to 6 square feet per 50 lb bag at 1 inch) and shows how to turn a bag's yield into the density to enter, which is lower than the calculator's default. The road page gained a tons-per-mile table by paved width and a lanes-and-shoulders example. The repair cost page shows how a mobilization fee makes a small patch cost far more per square foot, the milling page shows tons of millings to haul off and what is known about reusing them, and the tarmac quantity page sets Tarmac's published spread rates and layer thicknesses beside the calculator's results. The tarmac repair page now covers patches, edges and overbanding, and the tarmac surface page covers surface types, with its side panel corrected to match its price table. An overfill allowance of about 1 inch for cold patch was corrected to about half an inch, as the manufacturers specify, and a claim that tarmac is laid 20 to 25% thicker than the target was removed because we could not source it.
View pageContent Rebuilt the 44 state paycheck calculators around each state's own wages and rules
Each state paycheck page now works its example from that state's typical salary, the median annual wage for all occupations from the U.S. Bureau of Labor Statistics (May 2025), instead of the same $60,000 and $75,000 figures on every page. It adds a second example for a full-time worker at the state's minimum wage, and centres the take-home pay table and the neighboring-state comparison on the state's typical salary. The how-to steps now follow the state's own withholding entries, local taxes and payroll programs. The 9 states that do not tax wages, plus Montana, North Carolina, North Dakota and Oklahoma, gained sourced answers on topics such as final paychecks, pay frequency, tipped wages and breaks. The explanation of federal withholding and FICA, which used to repeat on every state page, now appears once on the Paycheck Calculators page.
View pageFix Made the Asphalt page's cost and thickness answers match the calculators
The installed prices on the Asphalt page were out of date and well below the ranges the asphalt cost calculators use, so they now quote the same planning ranges: about $7 to $15 per square foot for a new driveway and $3 to $7 for a resurfacing overlay. The per-ton and concrete prices were removed because we could not source them; the answer now tells you to get a local quote and enter it in the tonnage calculator. Thickness and driveway lifespan answers now match the tonnage and driveway cost pages: commonly 2 to 3 inches for a driveway and 20 to 30 years of life when maintained.
View pageImprovement Linked five calculators that were hard to reach from other pages
The 401(k) retirement calculator now suggests the employer match calculator, the employer match calculator suggests the solo 401(k) calculator for the self-employed, and the mortgage payoff calculator suggests the 401(k) early withdrawal calculator for anyone weighing a withdrawal to pay down a mortgage. The asphalt driveway cost calculator now links to the tree removal cost calculator, since clearing trees is a common site-prep cost before a new driveway. Hawaii and Alaska have no neighbouring states to link from, so the paycheck calculators they point to now link back: Maine and Kansas list Hawaii among similar states, and Florida and Nevada list Alaska.
View pageImprovement Reorganised the Asphalt hub and explained how Tarmac relates to Asphalt
The asphalt calculators are now grouped as Area & quantity, Cost estimates, Repairs and Converting units, and a new answer on the Asphalt page helps you choose between the merged tools. Three figures in its FAQ were corrected to match the calculators: one ton covers about 83, 55 and 41 square feet at 2, 3 and 4 inches, and a 1,000 square foot driveway at 4 inches needs about 24 tons, not 16 to 18. The Tarmac page now says how tarmac (UK) differs from asphalt (US) and links to the asphalt equivalents of its calculators. The road, square footage, resurfacing, driveway cost and milling calculators and the tarmac driveway cost calculator also gained links to related tools.
View pageContent Rewrote the Cost Calculators page as Home & Project Cost Calculators
The category holds one calculator, for tree removal, and the page now says so plainly instead of describing a larger set of tools. Its chooser lists the tree removal calculator and links to the asphalt driveway, resurfacing, repair and milling cost calculators and the tarmac driveway, repair and surface cost calculators. Two answers in the FAQ now describe how the tools work: they are formula-based planning estimates that do not use live prices, not figures reviewed against market rates on a schedule.
View pageImprovement Moved the loan calculator into Finance and renamed it the Auto & Personal Loan Calculator
The Loan Calculators category held a single tool, so it has been folded into the Finance calculators. The loan calculator has a clearer name, the Auto & Personal Loan Calculator, for what it does: monthly payment, total interest and a first-year payment schedule for a car or personal loan, with trade-in, down payment, sales tax and dealer fees. The Finance page now carries the table showing what the loan term costs, an illustrative 7.0% APR example, and the list of common mistakes when comparing loans. The old Loan Calculators addresses now forward to Finance.
View pageImprovement Combined the tarmac sub-base calculator into the MOT Type 1 Sub-Base Calculator
The Tarmac Sub-Base Calculator and the MOT Type 1 Calculator sized the same MOT Type 1 layer from area, depth and density, so they are now one page, the MOT Type 1 Sub-Base Calculator. You can enter length and width or a total area you already know, and the result now shows the loose volume to order for a compaction allowance of 15%, 20% or 25%, alongside tonnes, cubic metres and bulk bags. The page cites its density and compaction figures to published sources and keeps the guidance on laying sub-base under tarmac. The old tarmac sub-base address now forwards to it, and the Tarmac and Asphalt hubs link to this calculator and the bitumen calculator.
View pageImprovement Combined the asphalt overlay and paving cost calculators into the resurfacing and driveway cost tools
The Asphalt Overlay Cost Calculator and the Asphalt Resurfacing Cost Calculator priced the same job from the same two inputs, so they are now one page, the Asphalt Resurfacing & Overlay Cost Calculator, which also answers whether to choose an overlay or sealcoating. The Asphalt Paving Cost Calculator has become a Commercial / large area mode inside the Asphalt Driveway Cost Calculator: enter the total area and separate material and labor and prep rates to price a parking lot or road, alongside the single-rate driveway estimate. The old overlay and paving cost addresses now forward to these pages.
View pageImprovement Made the asphalt conversion calculators work in both directions
The Asphalt Tons to Cubic Yards Calculator now has a direction toggle, so one page converts tons to cubic yards and cubic yards to tons, and the separate Cubic Yards to Tons Calculator forwards to it. The Asphalt Volume Calculator became the Asphalt Volume & Weight Calculator: besides working out volume from length, width and thickness, it converts a volume you already know into tons, pounds and metric tonnes, and the separate Asphalt Weight Calculator forwards to it. The Asphalt Tons to Square Feet Calculator also runs both ways, from tons to coverage or from an area to the tons needed. While recomputing the examples we corrected the coverage per ton at 2 inches to about 83 square feet, and the rounding of a few results.
View pageImprovement Combined nine asphalt quantity and conversion calculators into the Asphalt Tonnage Calculator
The asphalt paving, parking lot, square feet to tons, resurfacing, driveway, per ton cost, pounds to tons, thickness and density calculators are now one tool. Driveway, Parking lot and Overlay presets fill in a starting thickness and waste allowance; you can start from length and width, a total area or a weight you already have, enter density in lb/ft³ or kg/m³, add a price per ton for the material cost, and read the result in US tons, metric tonnes, pounds, cubic yards and cubic feet. The page gains a units and density reference with the conversion factors, the density table and a thickness guide, and the old addresses now forward to it.
View pageImprovement Combined the asphalt area and square-footage calculators into one tool
The Asphalt Area Calculator and the Asphalt Square Footage Calculator both added up rectangular sections, so they are now one page, the Asphalt Square Footage & Area Calculator. It shows the total in square feet, square yards and square meters, has a Copy Result button, and keeps both worked examples: the parking lot with an island and the L-shaped driveway. The old area calculator address now forwards to it.
View pageContent Reworded the homepage and category pages to describe only what the site offers today
Removed wording about tools and categories that are not on the site, renamed the “Most popular” sections to “Featured” because that set is chosen editorially rather than from usage data, and replaced the Paycheck Calculators progress note with a plain statement of which states are covered and which are not.
View pageFix Corrected a spelling error in the ERA Calculator's description
The ERA Calculator's listing in the calculator directories read “Calcualte Earned Runs Average”. It now reads “Calculate earned run average (ERA) for pitchers.”
View pageFix Roth vs Traditional 401(k) calculator now uses 2026 federal tax brackets
The calculator and its worked examples were still using the 2024 tax brackets and standard deductions; they now use the 2026 figures from IRS Revenue Procedure 2025-32, and the examples, which had also named the wrong tax bracket for their incomes, have been recalculated.
View pageFix Roth vs Traditional 401(k) calculator now taxes the employer match on the Roth side
The page said the employer match was treated as pre-tax for both choices, but the calculator counted the match as tax-free on the Roth side, which overstated the Roth result and lowered the break-even tax rate whenever a match was entered. The match is now held as a separate pre-tax balance and taxed at your retirement rate in the head-to-head result, withdrawal comparison, break-even finder and year-by-year table, so a match no longer moves the break-even rate.
View pageFix Roth vs Traditional 401(k) calculator now counts your existing balances in both scenarios
Your current Traditional balance was only counted if you chose Traditional, and your current Roth balance only if you chose Roth, so money you had already saved tilted the result and the break-even tax rate toward one side. Both balances now appear in both scenarios with their own tax treatment, so they no longer affect which option comes out ahead.
View pageFix 401(k) Contribution calculator now uses 2026 federal tax brackets
The tax-savings and take-home figures were still based on the 2024 brackets and standard deductions; they now use the 2026 figures from IRS Revenue Procedure 2025-32, the same ones the Roth vs Traditional calculator uses. The worked examples were recalculated, which also corrected the first example's per-paycheck cost and the third example, which had applied the 24% rate to the whole contribution.
View pageFix 401(k) Early Withdrawal calculator now uses 2026 federal tax brackets
Federal tax on a withdrawal was still worked out with the 2024 brackets and standard deductions; it now uses the 2026 figures from IRS Revenue Procedure 2025-32. The worked examples were recalculated, correcting the Rule of 55 example, which had overstated the federal tax, and the lost-growth figure in the first example.
View pageFix 401(k) Loan calculator now quotes a dated prime rate
The page described the 2024 prime rate of 8.50% as current. It now quotes the Federal Reserve's published bank prime loan rate with its date, and the default loan rate is set one point above it.
View pageFix 401(k) Retirement calculator no longer describes its rules as 2024 rules
The page said it was built on 2024 IRS rules, but the calculator already uses the 2026 contribution limits. The description and the RMD section now say which rules apply instead of naming an out-of-date year.
View pageFix Footer no longer says nothing is stored
The footer on every page said nothing was stored, which overstated the privacy policy: analytics and advertising cookies may be set. It now says that nothing you type is stored, which is true because every calculation runs in your browser.
View pageImprovement Clearer privacy and consent information
The Privacy Policy now names the cookies and identifiers that Google Analytics, Google AdSense, Vercel Analytics and Ahrefs Analytics use, with a table of each one’s purpose. It also explains how visitors in the EEA, the UK and Switzerland are asked for consent, and how to change or withdraw that consent later. Google’s analytics and advertising tags now start with consent denied in those regions until the visitor makes a choice.
View pageImprovement Paycheck Calculators now cover 43 states and DC, with a state comparison table
The Paycheck Calculators hub now lists 43 states and the District of Columbia, with a comparison table of each one's tax type, top rate, local taxes and employee payroll deductions, a filter by tax type, and answers to common questions about working across state lines. Each state page also has its own share image. Indiana, Iowa, Kentucky, Massachusetts, Michigan, Mississippi and Ohio are not covered yet.
View pageNew tool Added Paycheck Calculators for eleven more progressive-tax states
Nebraska, New Jersey, New Mexico, North Dakota, Oklahoma, Rhode Island, South Carolina, Vermont, Virginia, West Virginia and Wisconsin join the Paycheck Calculators, each using its official 2026 withholding tables or formula. They include New Jersey's rate tables A to E with UI, disability and family leave deductions, Rhode Island TDI, Oklahoma's new 4.5% top rate, West Virginia's mid-year rate cut and Charleston, Huntington and Morgantown city service fees, and South Carolina's 2026 rate change noted alongside the withholding formula employers still use.
View pageNew tool Added Paycheck Calculators for New York, Maryland, Missouri and Oregon
New York, Maryland, Missouri and Oregon join the Paycheck Calculators, each using its official 2026 withholding method. They include New York City and Yonkers taxes, New York Paid Family Leave and disability insurance, Maryland's required county income tax for all 23 counties and Baltimore City, the Kansas City and St. Louis earnings taxes, and Oregon's federal-tax subtraction, Paid Leave Oregon, statewide transit tax and Portland-area Metro and Preschool for All taxes.
View pageNew tool Added Paycheck Calculators for ten progressive-tax states
Alabama, Arkansas, Connecticut, Delaware, the District of Columbia, Hawaii, Kansas, Maine, Minnesota and Montana join the Paycheck Calculators, each using its official 2026 withholding method (an estimate from the rate schedule for DC, which publishes none). They include Alabama's federal-tax deduction and Birmingham-area occupational taxes, Maine's August 2026 table revision, Montana's new 5.65% top rate, Wilmington's wage tax, and the CT, Delaware, Maine and Minnesota paid leave and Hawaii TDI deductions.
View pageNew tool Added Paycheck Calculators for eight flat-tax states
Arizona, Colorado, Georgia, Idaho, Illinois, Louisiana, North Carolina and Utah join the Paycheck Calculators, each using its state's official 2026 withholding method. They include Georgia's and Utah's mid-2026 rate cuts, Idaho's July 2026 table revision, Colorado's FAMLI premium and Denver-area occupational privilege taxes, and Arizona's Form A-4 percentage election.
View pageNew tool Added Paycheck Calculators, starting with California, Pennsylvania and Texas
New calculators estimate take-home pay after federal withholding, FICA, and state and local taxes for a salaried or hourly paycheck. The category launches with California, Pennsylvania and Texas — chosen to cover a progressive-tax state, a flat-tax state with local taxes, and a no-income-tax state — with the rest of the states following in batches.
View pageNew tool Added eight more Paycheck Calculators for states with no tax on wages
Alaska, Florida, Nevada, New Hampshire, South Dakota, Tennessee, Washington and Wyoming join the Paycheck Calculators. Alaska includes its 0.50% employee unemployment deduction, and Washington includes Paid Family and Medical Leave and WA Cares.
View pageNew tool Added the Scientific Calculator
The scientific keypad that used to sit part-way down the home page now has a page of its own, with the arithmetic unchanged and everything it does written down: which keys switch between degrees and radians, what Inv actually swaps, and where its behaviour differs from a handheld calculator. Three of those differences catch people out — the % key divides by 100 rather than taking a percentage of the number before it, powers group from the right so 2^3^2 is 512 and not 64, and a minus sign placed directly before a power is rejected outright. Each one is documented with the result you will actually see, along with the display limits: 10 decimal places, scientific notation past 1e10, and no memory keys beyond Ans.
View pageImprovement Rebuilt the home page around finding the right calculator
The home page used to dump all 57 calculators into one filtered grid, which made it long to scan and left the eight category pages almost unlinked. It now opens with a plain-language summary of what the site actually covers, a search box, and real links to each of the eight categories with their true tool counts — including the two that have a single tool, because rounding that up would be misleading. Below that: eight common jobs pointing straight at the tool that does them, a featured set chosen from what people actually search for rather than editorial guesswork, the most recently updated pages, how the calculators are built and sourced, and answers to the questions people ask about the site itself — who publishes it, what happens to the numbers you type in, and what it is genuinely best at.
New tool Added the Reverse Sales Tax Calculator
Enter what you were actually charged and a tax rate, and get the pre-tax price back. It also runs the common wrong method — subtracting the rate from the total instead of dividing by it — side by side, so the size of that mistake is a number rather than a warning. The rate is always yours to supply; the calculator holds no rate table for any state or locality.
View pageNew tool Added the Tip Percentage Calculator & Tip Chart
A percentage-first companion to the tip calculator: pick a rate before you have a bill in hand and see what it means in dollars across a few common bill sizes, plus a full $5–$200 tip chart at 10%, 15%, 18%, 20% and 25%. It also answers whether 15%, 18%, 20% or 25% counts as a good tip by checking each one against the same published range the rest of the category reads from — no invented average, because no source consulted publishes one.
View pageNew tool Added the Food Delivery Tip Calculator
Work out the tip for a restaurant, pizza or grocery delivery, or a takeout order you pick up yourself. The delivery fee is kept out of the tip calculation entirely, the published per-order minimum is applied automatically on small orders, and takeout/pickup reads its own, discretionary guidance rather than the delivery figure.
View pageNew tool Added the Tip and Sales Tax Calculator
Settles one question: do you tip on the subtotal or on the total including sales tax, and what does the choice cost? Both calculations run side by side rather than behind a toggle, with the difference given in dollars — it is the bill multiplied by both rates, so on a $50 bill at 8% tax with a 20% tip it comes to 80 cents. It also shows how an automatic gratuity interacts with sales tax, quoting California and New York, which publish different rules on exactly that point.
View pageNew tool Added the Overtime Pay Calculator
Work out your overtime rate and what a week with overtime actually pays under the federal 40-hour rule, with fractional hours, an optional double-time setting, and honest biweekly, monthly and yearly projections. Every statutory figure on the page is cited to the fetched text of the law itself, and every figure it outputs is gross pay — it deliberately makes no attempt at take-home estimates.
View pageNew tool Added the Tip Calculator
The first tool in the Tip Calculators category is live. It works out the tip and the total on any bill, splits it across a group so the shares always add back up exactly, handles sales tax either way round, and runs in reverse to recover the bill from a total you have already paid. Every tipping range it shows is quoted from a published etiquette source and linked.
View pageNew tool Added the Haircut & Salon Tip Calculator
Work out the tip for a haircut, colour, blow-dry, barber visit, manicure or pedicure, with a salon tip chart you can scan at the desk. It also does the thing no other salon tip calculator seems to: when two or three people worked on you, it shows one tip divided by what each person did and divided evenly, side by side, so you can see the difference before you choose. The page is explicit about where the published range stops — including the owner question, which is genuinely contested.
View pageNew tool Added the Bill Split Calculator
Split any bill three ways: evenly, by what each person actually ordered, or in proportion to income. It answers the question most bill splitters skip — whether the tip and the tax follow the bill or get shared equally per head — by showing both answers side by side, because on an itemised or income split they are not the same and the gap is real money. Every share is worked out in whole cents so the parts always add back up to the total, rounding up is shown as its own line rather than vanishing into the tip, and if somebody has already paid it works out the fewest payments that square everyone up. The income-weighting methods are named and their formulas shown, because there is no authority on what a fair split is and the page does not pretend otherwise.
View pageContent Upgraded the Tip Calculators hub to a full pillar page
The category page now opens with a plain-language answer and a guided tool chooser, and carries a sourced table of every published US tipping range the category uses — from restaurant table service to nail salons — plus category-level FAQs and the common mistakes people make when tipping and splitting.
View pageNew tool Launched the Tip Calculators category
A new category for working out tips, splitting bills, and figuring gratuity is now live. It opens as a category hub, with individual tip, bill-split, and salon tip calculators arriving in the days ahead.
View pageImprovement Improved on-site search to match calculator keywords, not just titles
Search now checks each calculator's full list of keywords, so a query like "tonnage" or "retirement limits" finds the right tool even when that exact word isn't in its title. The empty-search view now shows our real set of featured calculators plus a way to browse by category, replacing a fixed list and a dead-end "no results" message.
View pageImprovement Updated the site favicon to match our current logo
The icon shown in browser tabs and bookmarks now matches the logo used across the site, replacing an older, mismatched icon.
- Milestone
New tool Added a category menu and search to the site header
The top navigation now surfaces all 7 calculator categories in a drop-down menu, plus a direct link to search, so any tool on the site is reachable in two clicks from anywhere.
View pageContent Rebuilt all 8 category hub pages as full pillar pages
The asphalt, tarmac, financial, general, AP exam, cost, loan, and master calculator hubs now open with a plain-language answer, a guided tool chooser, and a sourced reference table, replacing the previous thin listing pages.
View pageImprovement Generated a unique preview image for every calculator category
Sharing a link to any category hub now shows a purpose-made preview image on social media and in chat apps, instead of one generic site-wide image.
Fix Corrected a date mismatch between the sitemap and the contact page
Our sitemap listed July 28 as the last-modified date for the contact page while the page itself displayed July 29. The two are now generated so they cannot disagree — a page's visible "Last updated" date and the date we report to search engines are always the same value.
View pageImprovement Cleared the final items from our pre-advertising review
Resolved the remaining accessibility, structured-data, and layout issues flagged during our internal site audit, including heading-order and link-labelling corrections on several calculator pages.
- Milestone
Content Expanded 33 calculator pages and 3 category hubs with full explanatory content
Rewrote our asphalt quantity, conversion, cost, and surface calculators — plus the financial, tarmac, and general tools — so each page explains the formula it runs, the assumptions behind its defaults, and the limits of its estimate, instead of presenting a bare input form.
View pageImprovement Strengthened our trust pages with clearer disclosures
Added explicit advertising and data-use disclosures to the privacy policy, and expanded the About page to state plainly who builds these tools, how they are verified, and where our expertise ends.
View pageUnder the hood Published llms.txt and opened the site to AI answer engines
Added a machine-readable catalog of every calculator at /llms.txt and explicitly permitted AI crawlers in robots.txt, so tools like ChatGPT, Claude, and Perplexity can find and cite our calculators accurately rather than guessing at them.
Fix Fixed incorrect "related tools" links on 7 calculator pages
Seven pages were suggesting related calculators from the wrong category. Corrected the links and added a compile-time check so a mismatched category can no longer reach the live site.
Under the hood Built a reusable content system for calculator pages
Introduced a shared set of content components so every calculator page presents its formula, worked example, and caveats in a consistent structure — the groundwork for the site-wide content expansion that followed.
- Milestone
New tool Published our Methodology page
A single page documenting how we build each calculator, which standards bodies our formulas follow (the IRS for 401(k) rules, the Asphalt Institute and ASTM for paving conventions, the College Board for AP scoring), how we handle cost estimates, and what our tools are explicitly not qualified to tell you.
View pageNew tool Added visible "Last updated" dates across the site
Every trust page now shows when it was last reviewed and by whom, drawn from the same record that generates the page's structured data so the visible date and the machine-readable one can never drift apart.
New tool Added on-site search
A search page that lets you find a calculator by name or keyword without going through the category hubs.
View pageFix Fixed misleading freshness dates in our sitemap
Our sitemap previously stamped every URL with the current build date, which told search engines that all 60+ pages changed every time we deployed. Each page now reports its own genuine last-modified date.
Under the hood Rebuilt structured data on a single connected schema engine
Consolidated per-page structured data into one connected graph with consistent publisher, author, and site entities, and corrected invalid category values that search engines were rejecting.
Improvement Corrected the All Calculators link in the top navigation
The main navigation link pointed to an outdated destination; it now goes straight to the full calculator catalog.
View pageImprovement Refreshed the financial calculators category page
Reorganized the financial category listing so the retirement, loan, and savings tools are easier to tell apart at a glance.
View page- Milestone
New tool Added the 401(k) calculator suite
Eight new retirement tools covering contributions, employer match, loans, early withdrawal, solo 401(k) plans, and a Roth-versus-traditional comparison — all following contribution and loan rules published by the IRS.
View pageImprovement Introduced the All Calculators hub and restructured categories
Added a single page listing every tool on the site, and reorganized the category structure so each calculator sits in one clear, predictable place.
View page New tool Added the Mortgage Payoff Calculator
Shows how extra payments change your payoff date and total interest, with a full amortization schedule and interactive charts.
View pageNew tool Added the CD Calculator
Calculates certificate-of-deposit maturity value and interest earned across compounding frequencies, with a visual breakdown of growth over the term.
View pageNew tool Added five tarmac calculators for UK paving projects
Quantity, sub-base, surface cost, driveway cost, and repair cost tools using UK paving terminology and metric units, for projects where our US asphalt tools don't quite fit.
View pageNew tool Added the MOT Type 1 Calculator
Estimates MOT Type 1 sub-base aggregate needed for a driveway or path, a standard first step in UK groundwork planning.
View pageNew tool Added the Bitumen Calculator
Estimates bitumen binder quantities for surface dressing and paving work, rebuilt on a modular structure with full supporting content.
View pageNew tool Added the Rounding Calculator
Rounds numbers to a chosen decimal place or significant figure, with the rounding rule applied shown explicitly so you can check the result.
View pageNew tool Added AP exam score calculators for Biology and Chemistry
Convert raw section scores into the College Board's published 1–5 AP scale, so students can estimate where a practice exam would land.
View pageNew tool Added the Cost Calculators and Loan Calculators categories
Two new category sections, opening with a tree removal cost estimator and a car and personal loan calculator.
View pageNew tool Added the EAR Calculator
Converts a nominal interest rate into the effective annual rate, making offers with different compounding schedules directly comparable.
View pageUnder the hood Added site analytics and refreshed the calculator layout
Enabled traffic analytics so we can see which tools people actually rely on, and tidied the shared calculator layout for consistency.
- Milestone
Launch OtherCalculators launched with a 25-tool asphalt suite
The site went live with a complete set of asphalt calculators covering tonnage, volume, weight, area, thickness, density, unit conversions, and cost estimating for driveways, parking lots, roads, patches, and resurfacing work.
View pageUnder the hood Sitemap generated automatically from the calculator catalog
Built the sitemap to derive directly from our calculator data, so a newly published tool is submitted to search engines without a manual step that could be forgotten.
Spotted something we should fix?
Corrections reported by readers are a real source of the entries above. If a formula looks wrong, a figure has gone stale, or a result doesn't match your own math, tell us — and if a change is warranted, it will show up on this page with the date it shipped.