How the binary to text converter works
In Binary → text mode, the converter cuts the digits into bytes — at each space if you separated them, or every 8 bits if you did not — and decodes the bytes as UTF-8 or ASCII. The result card shows the text, the number of characters and bytes, and the bytes in hex. The table below it lists each character with its code point and the exact bytes that produced it.
Text → binary does the reverse and lets you choose a space or nothing between bytes. Switching direction carries the result across, so you can check a round trip in one click. Separated groups of 7 bits are accepted too, because ASCII is often written that way. To read the same bytes as one number instead, use the binary to hex converter.
How text becomes bytes in UTF-8
Example: é is U+00E9, binary 000 1110 1001. It needs the two-byte form: 110 followed by the top 5 bits (00011), then 10 followed by the low 6 bits (101001), giving 11000011 10101001. The byte layout is defined in RFC 3629 (source: IETF).
Worked examples
Example 1 — decoding ASCII
- Binary:
- 01001111 01001011
- 01001111: 64 + 8 + 4 + 2 + 1 = 79
- 01001011: 64 + 8 + 2 + 1 = 75
- 79 and 75 in ASCII: O, K
Text: OK
Example 2 — encoding the euro sign
- Character:
- € (U+20AC)
- U+20AC in 16 bits: 0010 000010 101100
- Three-byte form: 1110xxxx 10xxxxxx 10xxxxxx
- Fill in the bits: 11100010 10000010 10101100
UTF-8 bytes: E2 82 AC
ASCII has no euro sign, so ASCII mode reports it instead of encoding it.
Common characters in binary (UTF-8)
| Character | Code point | UTF-8 bytes | Bytes |
|---|---|---|---|
| A | U+0041 | 01000001 | 1 |
| a | U+0061 | 01100001 | 1 |
| 0 | U+0030 | 00110000 | 1 |
| space | U+0020 | 00100000 | 1 |
| ! | U+0021 | 00100001 | 1 |
| é | U+00E9 | 11000011 10101001 | 2 |
| ñ | U+00F1 | 11000011 10110001 | 2 |
| € | U+20AC | 11100010 10000010 10101100 | 3 |
| 😀 | U+1F600 | 11110000 10011111 10011000 10000000 | 4 |
Key facts
- ASCII is a 7-bit character code with 128 characters, usually stored one per byte with the top bit set to 0.
- UTF-8 encodes each Unicode character in one to four bytes, and any ASCII text is byte-for-byte identical in UTF-8.
- In ASCII and UTF-8, capital A is 01000001 (65) and lowercase a is 01100001 (97); the two differ only in the bit worth 32.
- UTF-8 is limited to code points U+0000 to U+10FFFF, and the surrogate range U+D800 to U+DFFF is never encoded.
ASCII or UTF-8: which should you choose?
Choose UTF-8 unless you know you are dealing with 7-bit ASCII. Web pages, JSON and most modern files are UTF-8, and because its first 128 characters match ASCII, it decodes plain English correctly either way. ASCII mode is useful when you are checking that text contains no characters outside the original 128 — a legacy protocol, a strict file format or a classroom exercise on character codes. RFC 20 describes ASCII as a 7-bit code carried in an 8-bit byte whose top bit is always 0 (source: RFC 20), which is why every ASCII byte starts with 0.
Common binary to text mistakes
- A missing bit. Without spaces, the digits must be a multiple of 8. One dropped bit shifts every byte after it, so the converter refuses rather than producing nonsense.
- Reading UTF-8 bytes one at a time. 11000011 on its own is not a character; it is the first half of é. Decode the bytes together.
- Assuming one byte per character. “café” is 4 characters but 5 UTF-8 bytes, and a single emoji is 4 bytes.
- Confusing the digit with the number. The character “5” is 00110101 (53), not 00000101.
Frequently Asked Questions
What does 01001000 01101001 say?
It says “Hi”. 01001000 is 72, the code for capital H, and 01101001 is 105, the code for lowercase i. The two encodings agree here, because UTF-8 stores every ASCII character as the same single byte.
How do you convert binary to text by hand?
Split the bits into 8-bit bytes, turn each byte into a decimal number, and look the number up in an ASCII table: 65 is A, 97 is a, 48 is the digit 0 and 32 is a space. For characters outside ASCII, read the UTF-8 rules: a byte starting 110, 1110 or 11110 begins a 2, 3 or 4-byte character.
How many bits is one letter?
An English letter, digit or common symbol is 8 bits — one byte — in both ASCII and UTF-8. Accented letters such as é take 16 bits in UTF-8, the euro sign € takes 24, and most emoji take 32.
What is the difference between ASCII and UTF-8?
ASCII is a 7-bit code with 128 characters: English letters, digits, punctuation and control codes. UTF-8 encodes every Unicode character in one to four bytes, and its first 128 characters are identical to ASCII, so plain English text is the same in both.
Why does my binary give an error instead of text?
Either the length is not a whole number of bytes, or the bytes are not valid UTF-8 — for example a byte starting 10 with no lead byte before it, or a multi-byte character cut short. The converter names the byte that breaks the rule rather than guessing, so a typo is not silently turned into a different character.
Is binary to text the same as converting binary to a number?
No. 01000001 is the number 65 when read as an integer, and the letter A when read as ASCII text. The bits are the same; what they mean depends on how a program interprets them. Use the binary to decimal converter for the number.
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Notes & Assumptions
- Text input is limited to 2,048 characters, and every character is encoded exactly as UTF-8 or ASCII defines it.
- Broken UTF-8 — stray continuation bytes, cut-off characters, overlong forms and surrogates — is reported, not replaced with a substitute character.
- Other encodings such as UTF-16, Latin-1 or Windows-1252 are not decoded; bytes 128–255 are read only as parts of UTF-8 characters.
This tool is for education and general use. Check encodings used in production systems against the relevant specification.