How text is converted to binary
Computers store text as numbers. Each character has a code point (A is 65, a is 97, a space is 32), and an encoding decides how that number is stored as bytes. The web uses UTF-8 almost everywhere, so that is what this tool uses.
In UTF-8, the 128 ASCII characters (English letters, digits and common punctuation) take one byte each, so their binary is just the code written in 8 bits. Other characters take two to four bytes: é is 2 bytes, € is 3 and most emoji are 4.
Example 1: Hi → 01001000 01101001
Each character becomes one or more bytes
Every character has a code number. For ordinary English letters, digits and punctuation, UTF-8 stores it in a single byte, written as 8 bits.
| Character | Code point | UTF-8 bytes (hex) | Binary |
|---|---|---|---|
| H | U+0048 | 48 | 01001000 |
| i | U+0069 | 69 | 01101001 |
2 bytes
Example 2: Café → 01000011 01100001 01100110 11000011 10101001
Each character becomes one or more bytes
Every character has a Unicode code point. UTF-8 stores ASCII characters in 1 byte and other characters in 2 to 4 bytes. Each byte is then written as 8 bits.
| Character | Code point | UTF-8 bytes (hex) | Binary |
|---|---|---|---|
| C | U+0043 | 43 | 01000011 |
| a | U+0061 | 61 | 01100001 |
| f | U+0066 | 66 | 01100110 |
| é | U+00E9 | C3 A9 | 11000011 10101001 |
5 bytes
Where this comes up
- Computer science homework and exams that ask you to encode a word in ASCII or binary.
- Checking how many bytes a string really takes, for example when a database column or SMS limit counts bytes rather than characters.
- Puzzles, escape rooms and messages hidden in binary.
Frequently asked questions
Why does é turn into two bytes?
é is not an ASCII character. Its code point is 233, and UTF-8 stores any code point above 127 in two or more bytes, so é becomes 11000011 10101001. Older encodings such as Latin-1 used a single byte (11101001), which is why text sometimes looks garbled when the wrong encoding is used.
Is this ASCII or UTF-8?
Both, for plain English text. UTF-8 was designed so that the first 128 characters are stored exactly as in ASCII, one byte each. Only characters outside ASCII use more bytes.
What is the binary for a space?
A space is character 32, which is 00100000 in binary.
Is my text sent anywhere?
No. The conversion runs in your browser and nothing you type is uploaded.