Hexadecimal to Decimal
Convert a hexadecimal number to its decimal (base-10) value.
About the Hexadecimal to Decimal converter
This tool converts a hexadecimal number into the everyday base-10 value people are used to. Each position in a hex number is a power of sixteen, so FF means 15 times 16 plus 15, which is 255 in decimal. It is the natural way to read a colour code, memory address, byte value, or status code as a plain, comparable number.
How to use it
- Enter a hexadecimal number using 0-9 and A-F.
- The decimal equivalent appears immediately.
- Copy the result for your notes, code, or calculations.
A common use is turning a hex colour component such as FF into the 0 to 255 value used by RGB tools. The converter accepts upper or lower case letters, treats the input as an unsigned whole number, and handles very large values exactly, so 64-bit hex converts without rounding. A leading 0x prefix is just notation, not part of the number. Everything runs in your browser, so the values you enter are never uploaded.
Frequently asked questions
How is hexadecimal converted to decimal?
Each hex digit is multiplied by a power of sixteen based on its position, then summed. For example FF is 15 times 16 plus 15, which equals 255.
What do the hex letters A to F mean?
They are digit values above 9, where A is 10, B is 11, and so on up to F which is 15.
Does it handle very large hex numbers accurately?
Yes. Exact integer arithmetic is used, so even 64-bit hex values convert to decimal without rounding errors.
Is the hex I enter sent to a server?
No. The conversion runs entirely in your browser, so your input stays on your device.