Number Base Converter
Convert numbers between binary, octal, decimal, hexadecimal, and any base from 2 to 36. See step-by-step conversion breakdowns.
About Number Base Converter
This number base converter gives you instant, bidirectional conversion between binary, octal, decimal, hexadecimal, and any custom base from 2 to 36. Type a value in one field and all others update in real time.
All Common Bases in One View
The four most-used bases in programming and computer science each have their own input field: binary (base 2), octal (base 8), decimal (base 10), and hexadecimal (base 16). Edit any field and the rest sync automatically.
Custom Base Support
Need base 3 (ternary), base 12 (duodecimal), or base 36? Set the custom base field to any value from 2 to 36 and enter or read values in that base. This is useful for specialised applications in mathematics, computing, or puzzle solving.
Step-by-Step Breakdowns
For binary and hexadecimal conversions, the tool shows how the conversion works with a breakdown of positional values. This is helpful if you are learning number systems or want to verify the math behind a conversion.
If you mainly work with binary and decimal, the dedicated binary to decimal converter includes a bit visualisation. For hex-specific work, the hex to decimal converter has a focused interface.
All conversions happen in your browser using BigInt for arbitrary precision. No data is sent to any server.
Frequently Asked Questions
What bases does this converter support?
It supports any base from 2 to 36. The four most common bases - binary (2), octal (8), decimal (10), and hexadecimal (16) - each have dedicated fields. A custom base field lets you work with any other base in that range, using digits 0-9 and letters A-Z.
How does it handle very large numbers?
The converter uses BigInt internally, so it can handle arbitrarily large integers without losing precision. This makes it suitable for cryptographic values, large binary strings, or any number beyond the standard 64-bit integer range.
What digits are used for bases above 10?
Bases above 10 use letters after the digits 0-9. Base 11 uses 0-A, base 16 uses 0-F, and base 36 uses the full set of 0-9 plus A-Z. The reference table at the bottom shows all 36 possible digit characters and their values.
Why would I need to convert number bases?
Base conversion is common in programming (binary and hex for memory addresses, bitwise operations, colour codes), networking (IP addresses, subnet masks), digital electronics, and computer science education. Hex is also widely used for colour values in web design.
Can I convert in both directions?
Yes. Type a value into any field and all other fields update instantly. You can start from binary, decimal, hex, or any custom base and see the equivalent value in every other base simultaneously.