About the Number Base Converter
Convert integers between binary, octal, decimal, hexadecimal and any other base up to 36. Type in any field and the others update; numbers of any size are converted exactly.
Key features
- Binary, octal, decimal and hexadecimal
- Any base from 2 to 36
- Exact results for numbers of any size
- Accepts 0x, 0b and 0o prefixes
- Optional digit grouping
- Shows bits, bytes and the integer type it fits
Convert between number systems
Type a number into any field (binary, octal, decimal, hex or any base up to 36) and all the others update instantly.
Quick reference
| Decimal | Binary | Octal | Hex |
|---|---|---|---|
| 0 | 0 | 0 | 0 |
| 7 | 111 | 7 | 7 |
| 10 | 1010 | 12 | A |
| 15 | 1111 | 17 | F |
| 16 | 10000 | 20 | 10 |
| 255 | 11111111 | 377 | FF |
| 1024 | 10000000000 | 2000 | 400 |
| 65535 | 1111111111111111 | 177777 | FFFF |
Where you'll meet each base
- Binary (2): bits, flags and bitmasks.
- Octal (8): Unix file permissions like 755 (see the chmod calculator).
- Hexadecimal (16): colors (#FF8800), memory addresses, byte values and hashes.
- Base 36: compact IDs and short codes using 0–9 and A–Z.
Related tools
String to binary, string to hex, and Roman numeral converter.
How to use the Number Base Converter
- Enter your value in the fields above, or start from one of the examples or presets.
- Results update instantly as you type.
- Read the breakdown to understand each part of the result.
- Copy what you need with the copy buttons. Everything runs in your browser.