Hex to Decimal Converter

How the Hex to Decimal Converter Works

Hexadecimal is a base-16 number system that uses the digits 0–9 plus the letters A–F to represent values 10–15. This converter takes a hex value, accepts an optional 0x prefix, and returns the equivalent decimal (base 10) number along with the binary form.

The Method

Each digit in a hex number has a place value that is a power of 16. Reading right to left, the positions are worth 16⁰ (1), 16¹ (16), 16² (256), and so on. To convert:

Decimal = (digit value × 16ᵖᵒˢⁱᵗⁱᵒⁿ) summed across every digit

The letters map to numbers first: A=10, B=11, C=12, D=13, E=14, F=15.

Worked Example

Convert hex 2F9 to decimal:

Digit	Value	Position	Power of 16	Product
2	2	2	16² = 256	512
F	15	1	16¹ = 16	240
9	9	0	16⁰ = 1	9

Adding the products: 512 + 240 + 9 = 761. So hex 2F9 equals decimal 761.

Where You Will See Hex

Hexadecimal appears constantly in technology because it is a tidy shorthand for binary:

• Web colors — codes like #FF5733 are three hex pairs for red, green and blue.
• Memory addresses — debuggers and disassemblers show addresses in hex.
• Byte values — a single byte ranges from 00 to FF (0 to 255 in decimal).

Because each hex digit equals exactly four binary bits, the binary output makes the bit-level pattern of your value easy to inspect.