Number Base Converter

What This Converter Does

Numbers can be written in different bases. We normally count in base 10 (decimal) because we have ten fingers - each place is worth ten times the one to its right (ones, tens, hundreds). Computers count in base 2 (binary) using only 0s and 1s, where each place is worth two times the last (1, 2, 4, 8, and so on).

So the same amount can wear different “outfits”: the decimal number 10 is 1010 in binary and A in hex. The columns under the calculator show why - each digit is worth its face value times a power of the base, and adding those up gives the decimal value. Enter a number in any base and see it in all the common ones at once.

The Bases

Base	Radix	Digits
Binary	2	0-1
Octal	8	0-7
Decimal	10	0-9
Hexadecimal	16	0-9, A-F

How to Use It

1. Enter the value.
2. Choose the base it is written in.
3. Read the decimal, binary, hexadecimal, and octal forms.

Worked Examples

Value	From	Decimal	Binary	Hex
1010	binary	10	1010	A
255	decimal	255	11111111	FF
FF	hex	255	11111111	FF
10	decimal	10	1010	A

FAQ

How do you convert binary to decimal?

Each binary digit is a power of 2, added up from the right. 1010 is $8 + 0 + 2 + 0 = 10$.

What is hexadecimal used for?

Base 16 is common in computing — colors, memory addresses, and byte values — because each hex digit maps to exactly four binary digits.

Does it handle decimals or negative numbers?

It converts non-negative whole numbers. Enter a positive integer in the chosen base.