Free Binary to ASCII Converter

Paste binary and this binary to ASCII converter shows the character for each byte, with its decimal ASCII code next to it. It doubles as an ASCII translator and ASCII decoder for all 128 codes, including the invisible control characters most converters print as nothing. To decode a whole message with emoji or accents, use the binary code translator instead.

How to convert binary to ASCII

To convert binary to ASCII, split the binary into groups of eight digits (or seven, for 7-bit ASCII). Turn each group into a number using place values 128, 64, 32, 16, 8, 4, 2, 1. Then find that number in the ASCII table: 01001000 = 72 = H. New to place values? How to read binary walks through it step by step, with practice.

1. Split into bytes. 010010000110100100100001 becomes 01001000 01101001 00100001. Count before you split: 24 digits means three bytes. If you get 23, a digit went missing somewhere, and every byte after that point will decode to the wrong character.
2. Turn each byte into its ASCII code. 72, 105, 33. (In 01001000, the 1s sit under 64 and 8. Add them: 72.)
3. Look up each code in the table below. 72 is H, 105 is i, 33 is an exclamation mark. Hi!

Here’s a shortcut that catches a lot of mistakes. Every ASCII code is 127 or less, so the first digit of an 8-bit ASCII byte is always 0. A byte that starts with 1 isn’t ASCII at all, and no table on this page will have it.

Binary to ASCII table (0–127)

This is the full ASCII code translator chart: all 128 codes in 8-bit and 7-bit binary, with the decimal code for each. Type a character, a binary code or a number into the search box to jump to its row.

ASCII binary table. Every code checked against RFC 20.

Control characters: the invisible quarter of ASCII

Look at the first 32 rows and the last one. None of them is a character you can see. These 33 codes were commands for teleprinters and terminals: ring the bell, move the paper up a line, send the carriage back to the left. Some still do real work in every text file you open. The ones you’ll actually meet:

DEL is the odd one out, sitting alone at the very end. That’s because 1111111 means all seven holes punched on paper tape, and punching every hole was how you crossed out a mistake.

If your decoded text has gaps, or line breaks you didn’t type, a control code is usually why. 0010110 is a common one people paste in: it’s 22, called SYN, a control code rather than a letter.

Only need letters? The binary alphabet chart has A–Z on its own.

What about codes above 127?

ASCII stops at 127. That surprises people, because a byte can hold up to 255.

Codes 128 to 255 are often called “extended ASCII”, but there’s no single extended ASCII. Windows-1252 and Latin-1 are two different tables that both fill that range, and older systems used others. UTF-8, which almost every web page uses now, treats those bytes differently again: a byte above 127 is only ever one part of a longer character (RFC 3629).

Take 10101010, which is 170. In Windows-1252 and Latin-1 it’s ª, a small raised a. In UTF-8, on its own, it isn’t a character at all. That’s why this converter flags it instead of guessing. If your binary has accents or emoji in it, paste it into the binary code translator linked at the top of the page, which reads UTF-8.

ASCII to binary

ASCII to binary is the same lookup run backwards: find the character’s code in the table above, then write that number in 8 bits. Capital A is 65, so it becomes 01000001. To convert a whole message at once, type it into the text to binary converter.

Frequently asked questions

''.join(chr(int(b, 2)) for b in s.split())

s.trim().split(/\s+/).map(b => String.fromCharCode(parseInt(b, 2))).join('')

Every code in the table was generated and checked against RFC 20.

Sources: RFC 20, ASCII format for network interchange · RFC 3629, UTF-8