Every 8-bit group in your input is one byte, and each byte is a number between 0 and 255. The selected encoding — UTF-8 by default — maps those numbers back to characters. That is why 01001000 01101001 becomes Hi: 72 is H and 105 is i.

What this decoder handles for you

  • Messy formatting — spaces, commas, line breaks, 0b prefixes and b suffixes are cleaned automatically, with a report of what changed.
  • Continuous bits — 0100100001101001 without spaces is split into 8-bit bytes automatically.
  • Unicode and emoji — UTF-8 decoding turns multi-byte sequences back into Chinese characters and emoji.
  • Broken input — the Error Clinic locates the exact group with the wrong bit count or an illegal character, and offers one-click fixes.

Binary number or binary text?

A short fragment like 10101 is not a complete text byte. Instead of guessing, the decoder asks whether you meant the binary number 21. Read more in our guide to decoding binary by hand or the article about binary numbers vs binary text.