Number Base Converter
Convert a whole number between any two bases from 2 to 36, including binary, octal, decimal and hexadecimal.
Base converter
Pick the base you have and the base you want.
Result
ff
11111111
Binary (base 2)
377
Octal (base 8)
255
Decimal (base 10)
ff
Hex (base 16)
Private: Everything runs in this page. Nothing you type is sent anywhere or saved.
On this page
Base conversion examples
| Decimal | Binary | Octal | Hex |
|---|---|---|---|
| 10 | 1010 | 12 | a |
| 255 | 11111111 | 377 | ff |
| 1000 | 1111101000 | 1750 | 3e8 |
| 65535 | 1111111111111111 | 177777 | ffff |
| 18446744073709551616 | 10000000000000000000000000000000000000000000000000000000000000000 | 2000000000000000000000 | 10000000000000000 |
Formula
repeated division by the new base; the remainders are the new digits
How the base converter works
- Step oneType the number and choose the base it is written in.
- Step twoChoose the base you want. The tiles also show binary, octal, decimal and hex.
- Step threeDigits above 9 are written as the letters a to z.
What this tool does not do
- It converts whole numbers only, with no fractions.
- It does not set a fixed width, so leading zeros are dropped.
- Letters in the input are read in either case; the case of the output is your choice.
Frequently asked questions
How large a number can it handle?
Very large: the conversion works digit by digit, so it is not limited to the 15 or so digits a normal calculator keeps. The limit here is 2,000 digits.
Can I use negative numbers?
Yes, put a minus sign in front. Fractions are not supported.
What are the digits in base 16?
0 to 9 then a to f, where a is ten and f is fifteen.