Number base converter

Digits above 9 use letters: A = 10, B = 11, up to Z = 35.

Your answer

In base 211111111
Decimal255
Binary11111111
Octal377

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How we worked it out

Updated as you change the numbers.

  1. Convert to a whole number by summing digit × baseᵖᵒˢⁱᵗⁱᵒⁿ, then write it in the new base by repeated division.

Method and assumptions

Uses exact big-integer arithmetic, so long numbers convert without rounding.

Questions

What is FF in binary?

11111111 (255 in decimal).

Sources

Method and figures checked on . Every worked answer on this page is covered by an automated test. Found a mistake? Tell us.

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