Binary Translator

Marcus Vance, Contributing Writer, Technology & Mathematics · Updated July 8, 2026

The tool maps each character to its ASCII number, then writes that number in base 2, padded to 8 digits. Type or paste text into the top box and click Text to Binary: every character becomes an 8-bit group separated by a space. Do the reverse by pasting binary groups into the bottom box and clicking Binary to Text; the tool splits the string into 8-bit chunks, converts each to a decimal number, and looks up the matching ASCII character. It handles any standard ASCII character, including letters, digits, punctuation, and spaces, and if a binary group is not valid it reports exactly what went wrong instead of returning silent garbage.

Every character on a standard keyboard has an ASCII code: a number from 0 to 127, defined by the ASCII (ANSI X3.4) standard and preserved unchanged as the first 128 code points of Unicode / UTF-8. Binary writes that number in base 2 and pads it to 8 bits. A short excerpt:

Source: binary-ascii-reference-2026.csv, the same 128-row ASCII dataset the full reference table below is built from. The five rows above are a manual excerpt for a quick look.

The leftmost bit is the most significant. Uppercase A is 64 + 1 = 65, which in binary is 01000001. The full reference table, with methodology and a downloadable CSV, is on the 2026 Binary / ASCII Encoding Reference page.

Binary is the native language of digital computing: every file on a drive and every packet crossing a network is ultimately a stream of 0s and 1s. Programmers use it directly when working with permission flags and bitwise operators, computer science students meet it early, and it turns up whenever someone wants text that looks like noise to anyone not holding the decoder.

Not everyone lands here for the same reason, and the tool works in both directions, so it helps to know which box you actually need. A computer science student checking homework usually has plaintext and wants to confirm the binary a professor already gave them: type the word into text_in and compare. Someone who found a string of 0s and 1s on a forum, a puzzle, or an old email is doing the opposite job: paste it into binary_out and read what comes back. A programmer debugging a bit pattern from a log file wants both directions at once, converting back and forth until the byte boundaries line up. And a fair number of people just want to see their own name rendered as binary, which is the same text-to-binary operation as the homework case, just for fun instead of a grade.

If you want the reasoning behind either direction spelled out step by step, How to Convert Text to Binary and How to Convert Binary to Text walk through it by hand. If the question is really about the character set underneath all of this, What Is ASCII covers where the numbers come from in the first place.

The tool's own JavaScript does exactly what the guides describe, so it is worth checking against a real example instead of taking that on faith. Take the word "Hey". The script reads each character with charCodeAt(0), which returns its ASCII number: H is 72, e is 101, y is 121. Each number then goes through toString(2) to become binary, and padStart(8,'0') adds leading zeros so every character fills a full 8-bit byte regardless of how small its number is.

Run the numbers by hand and they match what the tool prints: 72 is 1001000 in raw binary, padded to 01001000. 101 is 1100101, padded to 01100101. 121 is 1111001, padded to 01111001. Joined with spaces, "Hey" becomes 01001000 01100101 01111001, which is exactly what the box on this page returns if you type it in. Decoding runs the same logic backward: split on spaces, parseInt(group, 2) turns each 8-bit group back into a decimal number, and String.fromCharCode() turns that number back into a letter.

The converter works on standard ASCII, the 0 to 127 range that covers English letters, digits, punctuation, and a few control characters. Stick to that range and every conversion is exact and reversible. Step outside it, with an emoji, an accented letter, or a symbol from another script, and the tool falls into UTF-8 behavior: those characters take two, three, or four bytes instead of one, so the neat one-character-per-8-bits pattern breaks and a naive decode will not round-trip cleanly. That is a property of Unicode itself, not a bug in the page.

Decoding also expects the format the tool itself produces: 8-bit groups separated by spaces. Binary pasted in without spaces, or grouped some other way, will not parse correctly, and the tool says so rather than guessing. Everything happens in your browser tab. Nothing you type gets sent anywhere or saved anywhere, which also means refreshing the page clears it for good.