How binary to text decoding works
Computers store text as numbers using ASCII, where each character has a code from 0 to 127. One character fits in 8 bits (a byte). To decode, split the binary into 8-bit groups, convert each group to its decimal value, then map that number to its character. 01001000 is 72 = H and 01101001 is 105 = i, giving Hi.
The pattern becomes predictable once you spot it. Uppercase letters run from 01000001 (A, 65) to 01011010 (Z, 90); lowercase sits exactly 32 higher, so every lowercase byte starts 011. Digits 0-9 occupy 48-57, and every printable ASCII byte begins with a 0 in the leading position.
How to use this calculator
Paste binary as 8-bit groups separated by spaces, one byte per character. The tool returns the decoded text. To convert a single binary number to a plain number instead, use the binary to decimal calculator.
Because the conversion runs in your browser, nothing you paste is uploaded or kept. Two formatting mistakes cause almost every failure: groups shorter than eight bits (a leading zero was trimmed somewhere) and missing spaces, which merge two characters into one unreadable block.
Binary to text reference
Example ASCII letters:
| Binary | Decimal | Char |
|---|---|---|
| 01000001 | 65 | A |
| 01001000 | 72 | H |
| 01100001 | 97 | a |
| 01101001 | 105 | i |
| 00100000 | 32 | space |
To see the math behind each byte, try the bits to bytes calculator.
Decoding a whole sentence works the same way, one byte per character including the spaces between words - 00100000 is the space itself, which is why a decoded message runs together if those bytes were stripped out. To go the other way and turn a sentence back into bits, use the text to binary converter.
Frequently asked questions
- What does 01001000 01101001 spell?
- Hi. 01001000 is 72 (H) and 01101001 is 105 (i) in ASCII.
- Why must binary be in 8-bit groups?
- Each ASCII character is one byte (8 bits), so the decoder reads one 8-bit group per character.
- How do I separate the bytes?
- Put a single space between each 8-bit group, for example 01001000 01101001.
- Does this support non-English characters?
- It decodes standard ASCII (codes 0–127). Extended or Unicode characters need multi-byte encodings not covered here.
- Is the binary I paste sent to a server?
- No. Decoding happens entirely in your browser with JavaScript, so nothing you paste is uploaded or stored. The text disappears as soon as you close or reload the page.