Number Base Converter
Enter a number in any base to instantly see its value in binary, octal, decimal, hexadecimal, and base-36.
How to use Number Base Converter
The Number Base Converter translates integers between any two number bases from 2 to 36, including the most common: binary (base 2), octal (base 8), decimal (base 10) and hexadecimal (base 16). It is an indispensable tool for low-level programmers working with bitfields, memory addresses, colour codes and network masks where switching between bases is a daily task.
- Enter the number you want to convert in the input field.
- Select the source base from the "From" dropdown (e.g., 16 for hexadecimal).
- Select the target base from the "To" dropdown (e.g., 2 for binary).
- The converted result appears instantly; all common bases are shown simultaneously.
- For negative numbers, use two's complement representation — toggle the bit-width selector (8, 16, 32 or 64 bits).
Your data never leaves your device — 100% private processing.
Why different number bases matter in computing
Computers store data as binary (base 2) bits, but binary is verbose for humans to read. Hexadecimal (base 16) compresses four bits into a single digit, making memory dumps and colour values like #FF5733 far more readable. Octal (base 8) groups three bits and appears in Unix file permission modes (755 = rwxr-xr-x). Understanding all three bases and their conversions is fundamental to low-level debugging, network configuration and embedded systems programming.
Hexadecimal in web development
Hexadecimal is ubiquitous in web development: CSS colour codes (#RRGGBB), Unicode code points (U+1F600), HTML character entities (♥) and HTTP response codes are all expressed in hex. A six-digit hex colour encodes three bytes: two hex digits each for red, green and blue channels, each ranging from 00 (0) to FF (255). The shorthand #RGB notation uses one hex digit per channel and is expanded by doubling each digit (#F80 = #FF8800).
| Decimal | Binary | Octal | Hexadecimal |
|---|---|---|---|
| 0 | 0000 | 0 | 0 |
| 4 | 0100 | 4 | 4 |
| 8 | 1000 | 10 | 8 |
| 10 | 1010 | 12 | A |
| 15 | 1111 | 17 | F |
| 16 | 10000 | 20 | 10 |
| 255 | 11111111 | 377 | FF |
Glossary
- Binary
- Base-2 number system using only 0 and 1, corresponding directly to on/off states in digital circuits.
- Hexadecimal
- Base-16 number system using digits 0–9 and letters A–F to represent values 0–15.
- Octal
- Base-8 number system using digits 0–7, historically used for Unix permissions and some assembly languages.
- Two's complement
- A binary encoding for signed integers where negative numbers are represented by inverting bits and adding 1.
- Nibble
- A group of 4 bits, conveniently represented by a single hexadecimal digit.
Related reading
Frequently Asked Questions
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Why use Number Base Converter?
- No installation — use directly from any browser
- Handles large inputs without crashing or timeouts
- Syntax highlighting and formatted output for readability
- Copy to clipboard shortcut for fast workflow integration
Common use cases
- Validate and format JSON responses from APIs
- Encode/decode Base64 strings during debugging
- Generate UUIDs for database seeds or test data
- Minify CSS or JavaScript before deployment
- Diff two code snippets to spot regressions
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