Base Converter
Convert a number between binary, octal, decimal, hexadecimal and any custom base up to 36 with exact big-integer math.
Runs 100% in your browser — nothing is uploaded.
Result
Formula
Positional notation: value = Σ dᵢ · bⁱ
About this calculator
The Number Base Calculator converts numbers between different bases (binary, octal, decimal, hexadecimal, and any custom base from 2 to 36) and performs arithmetic operations on numbers in any base. The calculator uses standard base conversion algorithms.
How to use
- 1
Enter the number you want to convert in the 'Value' field (e.g., 'ff').
- 2
Select the base of the input number from 'From base' (or choose 'Custom…' and specify the base).
- 3
View the converted results in Decimal, Binary, Octal, and Hexadecimal.
Frequently asked questions
What bases are supported?
Any integer base from 2 to 36. Digits 0-9 and letters A-Z are used for bases above 10.
Can I convert negative numbers?
Yes, negative numbers are supported. The minus sign is preserved in the output.
How do I perform arithmetic?
Select an operation (add, subtract, multiply, divide, modulo, power) and enter a second number. Both numbers are interpreted in the input base.
Please note: Results are estimates for general information only and are not professional or medical/financial advice.