How to use it
- Choose Text → binary or Binary → text.
- Type or paste your text or your 0s and 1s.
- For encoding, pick binary, hex or decimal and a separator.
- Copy the result, or send it back to the input to reverse it.
How text becomes binary
Computers store text as numbers. Each character is first turned into one or more bytes using the UTF-8 encoding, and each byte is a number from 0 to 255, which takes exactly 8 binary digits (bits) to write.
For plain English letters, digits and punctuation, one character is one byte, and the values match the classic ASCII table:
| Character | Decimal | Hex | Binary |
|---|---|---|---|
| A | 65 | 41 | 01000001 |
| a | 97 | 61 | 01100001 |
| H | 72 | 48 | 01001000 |
| i | 105 | 69 | 01101001 |
| ! | 33 | 21 | 00100001 |
| space | 32 | 20 | 00100000 |
| 0 | 48 | 30 | 00110000 |
So Hi! in binary is 01001000 01101001 00100001. Uppercase and lowercase letters differ by exactly one bit (the value 32), which is why A is 01000001 and a is 01100001.
Characters outside ASCII take more bytes: accented letters such as é use 2 bytes (16 bits), and most emoji use 4 bytes (32 bits). The tool shows the total number of bytes under the result.
Decoding binary back to text
Switch the direction to Binary → text and paste the code. The decoder is forgiving about formatting:
- Spaces, line breaks, commas and other separators between bytes are ignored.
- A
0bprefix in front of a byte is ignored. - The bits are read in groups of eight from the start.
It will stop with a clear message if something is off:
- Other characters in the input. Digits 2–9 or letters mean it isn't pure binary (it may be hex or decimal).
- Bit count not a multiple of 8. A digit is missing or extra somewhere; every byte must have exactly 8 bits, including leading zeros.
- Not valid UTF-8. The bytes don't form valid UTF-8, so the tool shows them decoded as legacy Western (Windows-1252) text instead, which is usually right for old ASCII-based data.
Binary, hex and decimal output
When encoding, you can choose how the bytes are written:
- Binary (8-bit):
01001000 01101001 - Hexadecimal:
48 69– each byte as two hex digits, common in programming and network tools. - Decimal bytes:
72 105– each byte as a number from 0 to 255.
The separator can be a space, nothing at all, or a new line per byte. Use no separator for compact strings and a new line when you want to paste the bytes into a spreadsheet column.
Everything is calculated in your browser; your text is never uploaded.
Where binary code shows up
- Computer science classes. Converting your name to binary is a classic exercise in how data is stored.
- Puzzles and escape rooms. Hidden messages in 0s and 1s are a popular clue.
- Gifts and design. Binary messages on bracelets, mugs or T-shirts. Check the bytes here before ordering.
- Debugging. Seeing the actual bytes of a string helps track down encoding problems, such as invisible characters or wrong quotes.
Related tools: the Morse code translator for dots and dashes, and the Unicode escape converter for code points like U+00E9.
Frequently asked questions
How do I convert text to binary?
Type your text with the Text → binary direction selected. Each character is converted to UTF-8 bytes and every byte is shown as 8 binary digits.
What is “hello” in binary?
01101000 01100101 01101100 01101100 01101111 – one byte for each of the five letters.
Why does an emoji produce 32 bits?
In UTF-8 most emoji take 4 bytes, and each byte is 8 bits, so one emoji becomes four groups of eight digits.
Why do I get an error when decoding?
The input must contain only 0s and 1s (plus separators), and the number of bits must be a multiple of 8. Check for a missing digit or for hex characters.
Is this the same as ASCII to binary?
For English letters, digits and punctuation, yes. UTF-8 matches ASCII for the first 128 characters and adds multi-byte codes for everything else.
Last updated: November 12, 2026