Number Base Converter
Convert numbers between binary, octal, decimal, and hexadecimal bases instantly.
Quick Reference
โข Binary (Base 2): uses digits 0-1
โข Octal (Base 8): uses digits 0-7
โข Decimal (Base 10): uses digits 0-9
โข Hexadecimal (Base 16): uses digits 0-9 and letters A-F
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What is this tool?
Number base converter transforms values between different numeral systems: binary (base 2), octal (base 8), decimal (base 10), hexadecimal (base 16), and other bases (2-36). Shows real-time conversion across all bases simultaneously. Essential for programmers working with bit manipulation, memory addresses, color codes, and low-level data representation.
How to use
- 1
Enter number
Type a number in any base.
- 2
Select input base
Choose the source base (2-36).
- 3
View all bases
See the value converted to all common bases simultaneously.
Frequently Asked Questions
Why do programmers use hexadecimal?
Hexadecimal (base 16) is a compact representation of binary. Each hex digit maps to exactly 4 bits, making it easy to read and write binary data. 0xFF = 11111111 in binary. It is used for color codes (#RRGGBB), memory addresses, hash values, and byte-level data. Hex is much more readable than raw binary while being a direct mapping.
Can I convert floating point?
Integer is exact. Float may have precision limits.
How accurate are the conversions?
Conversions use standard conversion factors with high precision. For scientific applications use certified tools.
What is a number base?
A number base (or radix) is the count of digits a system uses before it rolls over. Binary is base 2 (0 and 1), octal is base 8, decimal is base 10 (the system this page is written in), and hexadecimal is base 16 (0-9 plus A-F). Each digit position is worth a power of the base, so in base 16 the value FF equals 15ร16 + 15 = 255. This tool converts a number to all four bases at once so you can compare them side by side.