What does this tool do?
The Number Base Converter instantly translates a value between decimal (10), binary (2), octal (8) and hexadecimal (16). Type into any field and the other three update automatically, plus it shows the bit count, byte count and whether the number is even. It is handy for programmers, students and anyone working close to the hardware.
How to use it
- Enter your values into the fields.
- The result is calculated instantly.
- Read or copy the result.
Four bases, one screen
The tool displays a single value in four bases at once: decimal, binary, octal and hexadecimal. Whichever field you edit becomes the source, and the other three are recomputed from it; enter 255 and you immediately see 11111111, 377 and FF. Hexadecimal input is uppercased automatically, and if you type an invalid character the tool flags the specific base instead of silently failing. Each field has its own copy button, so pasting a result into code takes only seconds.
Quick bit reference
The summary box beneath the fields reports how many bits represent the number, how many bytes it fits into, and whether it is even or odd. This is useful when working with memory alignment, bit masks or hardware registers, letting you see at a glance whether a value fits in a single byte. Everything is computed in your browser, so no data ever leaves your machine.
Frequently asked questions
Can I enter hexadecimal in lowercase?
Yes. Whether you type ff or FF makes no difference; the tool uppercases your input automatically and always presents hexadecimal results in uppercase.
Are negative numbers or fractions supported?
No. The converter works with non-negative integers. If you enter a negative or invalid value, it shows an error for the affected base.
How are the bit and byte counts calculated?
The bit count is the length of the binary representation; the byte count divides that by 8 and rounds up. For 255 you therefore see 8 bits and 1 byte.
Is Number Base Converter free?
Yes. Number Base Converter and all 300+ tools on MagmaNex are completely free with no signup or account required.
Is my data safe?
Yes. Everything runs locally in your browser. The data you enter is never sent to a server, stored, or shared.
Does it work on mobile?
Yes. Number Base Converter works on phones, tablets and desktops — no app download needed.
🔒 Privacy: everything runs in your browser, your data is never sent to a server.