Enter an integer
The table updates as you type. No button.
All bases
| Unit | Value |
|---|
When you need a number-base converter
Type an integer in the system you already have — decimal, binary, octal or hex. The table shows the same number in the other three.
Hex uses 0–9 and A–F. Binary is only 0 and 1. Spaces and prefixes like 0x or 0b are ignored. A minus sign stays a minus: −10 in decimal is −A in hex.
The number and the system sit on separate rows so a phone does not hide what you picked.
Nothing is sent to a server. There is no Calculate button.
The simple facts
The page reads the digits in the chosen base, then writes the same integer in the other three. You do not need the powers-of-two table to use it.
How to convert between number bases
- Type the value: Type the number as you already have it — 255, FF, 11111111.
- Pick the source unit: Choose the system on the row below: 2 binary, 8 octal, 10 decimal or 16 hex.
- Read every conversion: Read the same value in the other three systems. Your base is marked.
Frequently asked questions
How do I convert binary to decimal?
Choose Binary, type the 0s and 1s. 11111111 is 255 in decimal. The table shows octal and hex at the same time.
What does 0x mean?
A prefix that means “this is hex”. 0xFF and FF are the same here — the page strips 0x, and 0b / 0o for binary and octal.
Can I convert fractions like 0.5?
No. Integers only. A decimal point is rejected. For scientific notation, use that converter.
Is hex the same as hexadecimal?
Yes. Hex is the short name. Digits run 0–9 then A–F.