Number base converter
Convert integers between bases 2–36 without losing large-number precision.
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Result
Ready when you areEnter your input and run the tool to see your result here.
Good to know
Enter values without prefixes, such as FF or 1010. Negative integers are supported; fractions are not. BigInt preserves values beyond JavaScript Number’s safe integer range.
Input: FF From base: 16 To base: 10
Understand and use your results
Compare binary, decimal and hexadecimal integers during development. Integer strings are processed without first converting them to a potentially imprecise JavaScript Number.
How to use it
- Set source and destination bases between 2 and 36.
- Enter digits without prefixes such as 0x. A leading minus sign is supported.
Worked example
FF (base 16) → base 10
255
Hexadecimal F is 15, so FF means 15 × 16 + 15 = 255. Decimal 255 becomes 11111111 in binary. Each digit must be valid in the source base.
What if I enter 2 in binary or a fraction?
Binary permits only 0 and 1, so 2 produces an error. Fractions are unsupported. Leading zeros are not preserved as formatting; check the required width separately for fixed-width identifiers.