Decimal to duodecimal (base 12) converter

Type a decimal number and see it in duodecimal (base 12) right away, with the working shown. Useful for math and computer science students checking an exercise.

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How to use it

  1. Enter decimal number.
  2. The result appears straight away and updates as you edit.
  3. Copy the result, or copy a link that keeps the same values to share it.

How it is calculated

Repeated division: n = q × 12 + r, where the remainder r (0 to 11) is the next digit from the right; repeat on q until it reaches 0. Example: 2026 = 120A in base 12.

Example

Inputs: Decimal number = 2026. Result: Result in base 12: 120A; Number of digits: 4.

2026
120A

Limits and caveats

  • Whole numbers only, up to 1000 digits. For fractions use the fractional base converter.
  • The step table appears when the result has 60 digits or fewer.

Questions about this tool

How do I convert decimal to duodecimal by hand?

Divide by 12 and write down the remainder, then divide the quotient by 12 again until it reaches 0, and read the remainders from last to first. For example 2026 becomes 120A.

Why do some people prefer duodecimal?

Twelve divides by 2, 3, 4 and 6, so a third is 0.4 and a quarter is 0.3 with no repeating digits. The dozen (12) and the gross (144, written 100 in base 12) come from it.

Does it handle large and negative numbers?

Yes. It uses exact whole-number math up to 1000 digits with no rounding, and the result uses the digits 0 to 9 and the letters A to B. A negative number is converted by its absolute value and keeps its minus sign.