Number Base Converter
Convert between binary, octal, decimal, and hex — live.
How to use
Choose the base of your input, type the number, and all four representations update live below. Click any value to copy it.
About this tool
Enter a number in any base — binary, octal, decimal, or hexadecimal — and instantly see it in all the others. Great for debugging, bit math, and reading hex dumps. It runs entirely in your browser with arbitrary-precision integers, so large values stay exact.
What you can use Number Base Converter for
- Convert a hex color or byte value to decimal
- Read a binary flag value as hex
- Check an octal file-permission value in decimal
- Convert a large decimal id to hexadecimal
Frequently asked questions
Which bases are supported?
Binary (base 2), octal (base 8), decimal (base 10), and hexadecimal (base 16), converting in every direction.
Does it handle very large numbers?
Yes. It uses JavaScript BigInt, so even numbers far beyond 64 bits convert exactly without rounding.
Is my input sent to a server?
No — all conversion happens locally in your browser.
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