Number Base Converter
Convert between binary, octal, decimal and hexadecimal live.
About the Number Base Converter
The Number Base Converter shows the same value in binary, octal, decimal and hexadecimal at once. Type into any field and the other three update instantly, with validation that rejects digits that do not belong to that base (for example a '2' in a binary field). It is a daily helper for programmers working with colors, bit masks, memory addresses and file permissions. The conversion is done locally in your browser.
How to use it
- Type a value into whichever base you have — decimal, binary, octal or hex.
- The other three fields convert automatically as you type.
- Clear a field to reset the others.
Frequently asked questions
Which bases are supported?
Binary (base 2), octal (base 8), decimal (base 10) and hexadecimal (base 16) — the four bases programmers use most.
Is hexadecimal case-sensitive?
No. You can type hex digits in upper or lower case; the output is shown in uppercase for readability.
Does it work offline / privately?
Yes. All conversions run in your browser with no network calls, so nothing you enter is uploaded.
Related tools
JSON Formatter & Validator
Beautify, minify and validate JSON in your browser.
Developer ToolsBase64 Encoder & Decoder
Encode text to Base64 or decode it back instantly.
Developer ToolsURL Encoder & Decoder
Percent-encode or decode URLs and query parameters.
Developer ToolsUUID Generator
Generate random version 4 UUIDs in bulk.
Developer Tools