The number base works like this: it converts integers between binary, octal, decimal and hexadecimal with live digit grouping. Everything happens on your device - the input never leaves your tab unless the tool clearly states it performs a server-side lookup.
How to use the Number Base
Enter or paste the source value.
Confirm the source and target units or formats.
Read the converted result, which updates live as you type.
Copy the output when you are happy with it.
Features
Binary to decimal, hex, octal number converter
Instant result, no page reload
Works in any modern browser, desktop or mobile
Free with no signup
Common mistakes to avoid
Selecting a near-neighbor unit instead of the intended one
Forgetting whether a value is a rate or a total
Examples
Input
Result
255
binary 11111111 · octal 377 · hex FF
Best used for
Getting a reliable answer for number base without installing an app
One-off tasks done in under a minute from any device
Checking results before committing them to something important
Working on a phone where desktop software is unavailable
Privacy
Conversion runs locally in your browser tab.
Frequently asked questions
Can it handle fractional numbers?
It converts integer values; fractional conversion works differently per base and is intentionally excluded to avoid rounding confusion.
What number bases are supported?
Binary (base 2), octal (base 8), decimal (base 10) and hexadecimal (base 16), all converting live from whichever field you are editing.
How large a number can it handle?
Integers up to JavaScript's safe 53-bit range (9,007,199,254,740,991 in decimal) convert exactly; beyond that, digit grouping still displays but precision beyond 2^53 is not guaranteed.