Number Base Converter
Runs locallyConvert numbers between binary, octal, decimal, hexadecimal and any base from 2 to 36.
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Enter a number in any base from 2 to 36 and instantly see it in binary, octal, decimal and hexadecimal. Big values are supported exactly thanks to arbitrary-precision integers. Runs entirely in your browser.
Frequently asked questions
Which bases can I convert between?
Any base from 2 to 36 as input, with instant output in binary, octal, decimal and hexadecimal.
Does it handle very large numbers?
Yes. Arbitrary-precision integers are used internally, so 64-bit values and beyond convert exactly — no floating-point rounding.
Is my input uploaded?
No. Conversion is pure local arithmetic in your browser.