JSON formatter & validator
Format, beautify, validate, and minify JSON online. Pinpoint syntax errors by line and column, sort keys, and copy or download the result.
Number base converter
Convert numbers between binary, octal, decimal, hexadecimal, and any base from 2 to 36. Handles huge integers and negative numbers.
How to use Number base converter
Convert numbers between binary, octal, decimal, and hexadecimal — or any base from 2 to 36. Type in any field and the others update instantly.
- Arbitrary-precision integers, so very large values stay exact
- Negative numbers and prefixes like
0x,0b, and0o - Two's complement view for 8, 16, 32, and 64-bit integers
Number base converter FAQs
Is Number base converter free?
Number base converter is a free online tool on ReallyUseful.Tools. No account is required.
Does Number base converter run in my browser?
Number base converter is designed to run in your browser where supported, so files can stay on your device instead of being uploaded to a server.
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