Binary Translator
Convert between text and binary. Free, no signup.
How It Works
Type text in the top field to see its binary representation, or paste binary (space-separated 8-bit bytes) in the bottom field to convert it back to text. Both directions update instantly, and nothing is uploaded to a server.
Binary of Common Characters
| Character | ASCII | Binary |
|---|---|---|
| A | 65 | 01000001 |
| a | 97 | 01100001 |
| 0 | 48 | 00110000 |
| space | 32 | 00100000 |
| ! | 33 | 00100001 |
Numbers in Binary, Including -1
This translator turns text into binary, so typing -1 gives the two characters “-” and “1”: 00101101 00110001. When you type a whole number, the tool also shows the number itself in binary.
Computers store negative whole numbers in two's complement: write the positive number in binary, flip every bit, then add 1. For −1 that's 00000001 → 11111110 → 11111111.
| Number | 8-bit two's complement |
|---|---|
| 127 | 01111111 |
| 1 | 00000001 |
| 0 | 00000000 |
| −1 | 11111111 |
| −2 | 11111110 |
| −5 | 11111011 |
| −128 | 10000000 |
With more bits, a negative number just gets more 1s in front: −1 is sixteen 1s in 16 bits (FFFF in hex) and thirty-two 1s in 32 bits (FFFFFFFF). Two older conventions also appear in textbooks: sign-magnitude, where −1 is 10000001, and ones' complement, where it is 11111110. To convert positive numbers between binary, decimal and hex, use the Number Base Converter.
What Is Binary Code?
Binary is the base-2 number system computers use, made up of only 0s and 1s. Text is stored as binary by mapping each character to a number through the ASCII or Unicode standard, then writing that number in base 2 as an 8-bit byte. Translating between text and binary makes that hidden representation visible — handy for learning, puzzles, and computer-science exercises.
Frequently Asked Questions
How do I translate text to binary?
Type or paste your text into the Text field. Each character is converted to its 8-bit binary code and shown in the Binary field, with bytes separated by spaces. Copy the result with the Copy Binary button.
How do I convert binary to text?
Paste space-separated binary bytes (groups of 8 ones and zeros) into the Binary field and the decoded text appears in the Text field instantly. Both directions update live.
What is 'Hello' in binary?
Hello in 8-bit ASCII binary is 01001000 01100101 01101100 01101100 01101111 — one byte per letter: H, e, l, l, o.
What is -1 in binary?
As a number, -1 is 11111111 in 8-bit two's complement, the way computers store negative numbers. In 16 bits it is sixteen 1s (FFFF in hex) and in 32 bits thirty-two 1s (FFFFFFFF). Typed as text, -1 is two characters instead: 00101101 00110001.
How does binary code represent letters?
Each character maps to a number via the ASCII/Unicode standard (for example A is 65), and that number is written in base 2 as an 8-bit byte. So A becomes 01000001. Text is just a sequence of these bytes.
Is my text private?
Yes. The translation runs entirely in your browser using JavaScript — nothing is uploaded to a server, so your text stays on your device.