Convert Binary is a free online tool that turns plain text into its binary representation and turns binary strings back into readable text. Every character you type is converted into an 8-bit group of 0s and 1s (a byte), and the groups are separated by spaces so the output stays readable and unambiguous. This is a text-encoding tool, not a number-base calculator — if you're looking to convert a numeric value like 42 into binary, decimal, hex, or octal, use the separate Binary To Decimal converter instead. This tool is specifically about turning characters — letters, punctuation, symbols — into their binary byte representation and back.
Under the hood, every character your computer displays is really just a number, defined by a character encoding standard. The original ASCII standard assigned every English letter, digit, and common symbol a number from 0 to 127, which fits in 7 bits. Modern systems almost universally use 8-bit bytes instead, both because hardware is byte-addressable and because it leaves room for extended characters (accented letters, currency symbols, and more) in the 128-255 range. When you type "Hi" into this tool, it looks up the code point of 'H' (72) and 'i' (105), and renders each as an 8-bit binary string: 01001000 and 01101001.
This kind of encoding shows up in a surprising number of real contexts: computer science courses that teach how text is actually stored, capture-the-flag (CTF) security challenges that hide a flag inside a string of 1s and 0s, hobbyist projects that transmit short text messages over serial ports or simple RF links, and puzzle games or riddles built around binary code. It's also a useful teaching tool for understanding why character encoding bugs happen — an off-by-one bit or a mismatched byte width is often the root cause of garbled text (mojibake) when moving data between systems.
Both directions of the conversion run entirely in your browser using native JavaScript string and character-code methods. Nothing you type — whether it's a message you're encoding or a binary string you're decoding — is ever transmitted to a server.
