Decimal to vigesimal (base 20) converter
Type a decimal number and see it in vigesimal (base 20) right away, with the working shown. Useful for math and computer science students checking an exercise.
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How to use it
- Enter decimal number.
- The result appears straight away and updates as you edit.
- Copy the result, or copy a link that keeps the same values to share it.
How it is calculated
Repeated division: n = q × 20 + r, where the remainder r (0 to 19) is the next digit from the right; repeat on q until it reaches 0. Example: 2026 = 516 in base 20.
Example
Inputs: Decimal number = 2026. Result: Result in base 20: 516; Number of digits: 3.
2026
516
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 vigesimal by hand?
Divide by 20 and write down the remainder, then divide the quotient by 20 again until it reaches 0, and read the remainders from last to first. For example 2026 becomes 516.
Where was base 20 used?
The Maya counted in twenties, and a trace survives in French, where quatre-vingts (80) literally means four twenties.
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 J. A negative number is converted by its absolute value and keeps its minus sign.