Number Base Converter
Developer ToolsBinary / Octal / Decimal / Hex
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History
All history →Number Base Converter — at a glance
Convert a number between binary, octal, decimal and hexadecimal. Type in any box and the rest update.
255
Convert
Binary: 11111111
Octal: 377
Hex: FF
How to use it — step by step
Useful for programming, networking, electronics and computer science homework.
1
Type a number
Enter it in whichever base you know — binary, octal, decimal or hex.
2
See all bases
The other three fields fill in automatically.
3
Copy
Copy any value you need.
Pro tips
Small things that make the result better.
✦Binary uses only 0 and 1.
✦Hex uses 0–9 and A–F (A = 10 … F = 15).
✦Colors like #FF0000 are hex numbers: FF = 255.
Quick facts
Base 2binary — 0 and 1
Base 8octal — 0 to 7
Base 10decimal — normal numbers
Base 16hex — 0–9, A–F
Frequently Asked Questions
Why do computers use binary?+
Electronic circuits have two states — on and off — which map perfectly to 1 and 0.
Why is hex popular?+
One hex digit equals exactly 4 binary digits, so long binary numbers become short and readable.
Does it support negative numbers or fractions?+
It is built for whole positive numbers.
Is this tool really free?+
Yes — completely free, no signup, no watermark and no usage limit.
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