Text to Binary Converter — Binary, Hex, Octal & Back

Convert text to binary, hexadecimal, octal or decimal byte codes — and convert any of those back to text. The conversion works on the text's actual UTF-8 bytes, so accented letters, symbols and emoji come out as the multi-byte sequences a file or network really contains, and decode back to the same characters.

Paste separated codes or one continuous run of digits; both are understood.

How to use Text to Binary Converter

Choose the direction — Text → code, or Code → text.
Pick the format: binary, hex, octal or decimal.
Type or paste. Output updates live; the counters show characters, bytes and bits.
Copy, or Swap to feed the output back in and confirm it round-trips.

How text becomes numbers

A computer stores text as bytes, and a character encoding says which bytes mean which characters. Today that encoding is UTF-8 essentially everywhere. ASCII characters — the Latin alphabet, digits, common punctuation — are one byte each: H is 72, which is 01001000 in binary or 48 in hex. Everything else takes more: é is two bytes (C3 A9), € is three, an emoji is four. Converters that treat each character as one byte are wrong for every one of those, and this one is not.

Reading the four formats

Binary — eight digits per byte, always padded. 01001000, never 1001000; the leading zero is data.
Hexadecimal — two digits per byte, the compact way to write the same bits. What you see in hex editors and \x48 escapes.
Octal — three digits per byte, capped at 377. Survives in \110-style escapes and Unix permissions.
Decimal — the byte's value in ordinary numbers, 0–255. Readable, but needs separators: 72105 could be 72 105 or 7 210 5, so decimal input must be space- or comma-separated.

Decoding forgivingly

Codes may be separated by spaces, commas, newlines or nothing at all. A continuous run is split into fixed-width chunks — 8 binary digits, 2 hex, 3 octal — so 0100100001101001 decodes as Hi. Prefixes like 0x and 0b are stripped. Anything that is not a valid digit, or a value above 255, is reported with the exact token that failed rather than silently dropped; and bytes that do not form valid UTF-8 are reported as such instead of being replaced with question marks.

Related conversions

To convert a single number between bases (rather than each byte of a text), use the number base converter. To encode text or files for transport in a printable form, Base64 is the standard answer — six bits per character instead of eight binary digits per byte.

Frequently asked questions

Why does "é" become two binary numbers?

Because in UTF-8 — the encoding of essentially all modern text — é is stored as two bytes, C3 A9. One "character" is not one byte once you leave plain ASCII; emoji are four bytes. The converter shows what a file or network actually carries, and decodes those bytes back to the right character.

Do I need spaces between the binary bytes when decoding?

No. A continuous string is split into 8-digit chunks (2 for hex, 3 for octal), as long as its length is a multiple of that width. Decimal is the exception — 72105 is ambiguous — so decimal bytes must be separated.

What is "binary code" for a letter?

Its byte value written in base 2. Capital A is 65, so 01000001; lowercase a is 97, 01100001 — note the single bit (value 32) that differs between cases. Type the alphabet to see the pattern.

Why is my hex input rejected with "not valid UTF-8"?

The digits are fine but the bytes they describe don't form a valid text sequence — often because the source was a different encoding (Latin-1, UTF-16) or isn't text at all (a hash, a binary file). Rather than showing question marks, the tool says so.

How is this different from Base64?

Binary/hex/octal show each byte as a number — readable, but two to eight characters per byte. Base64 is a compact transport encoding (four characters per three bytes) designed for embedding binary data in text. For that, use the Base64 tool.