Hex Calculator
Convert a hexadecimal integer to decimal, write a decimal integer in hex, or do integer arithmetic on two hex values.
How it works
Hexadecimal is base 16. Digits run 0–9 then A–F (10–15). FF₁₆ = 15×16 + 15 = 255. Arithmetic is integer-only and stays inside the safe-integer range so the hex spelling and the decimal agree.
Division must come out exactly; 5 ÷ 2 has no hex integer result on this page. Case does not matter: ff and FF are the same number.
Formula
FF₁₆ = 15×16 + 15 = 255₁₀ A₁₆ × 2₁₆ = 14₁₆ (10 × 2 = 20)
Worked examples
Decimal to hex
255 → ff
Multiply two hex numbers
A × 2 → 14 (decimal 20)
Useful notes
- This is not a color-picker and does not parse #RRGGBB strings with a leading hash.
- For base 2 instead of base 16, use the binary calculator.
FAQ
- What letters are valid in hex?
A through F, in either case. A is 10, B is 11, …, F is 15.
- How do I convert hex to decimal?
Expand by place value. 1A = 1×16 + 10 = 26.
- Can I enter a hash color like #FF8800?
No. Drop the # and treat each channel separately, or paste the hex integer without decoration.
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