Convert octal to binary
17 in octal
1111
How it gets there
- Each digit carries its place
- 1 × 8¹ + 7 × 8⁰
- Which is
- 8 + 7 = 15
- Divide by 2, keeping the remainders
- 15 ÷ 2 = 7 remainder 1 7 ÷ 2 = 3 remainder 1 3 ÷ 2 = 1 remainder 1 1 ÷ 2 = 0 remainder 1
- Read the remainders upwards
- The last remainder is the leading digit.
Why the working is here
Every other converter of this kind prints the answer and stops. A base is a positional system, so the answer is a sum you can check: each digit is multiplied by the base raised to its position, and the results are added. Going the other way is repeated division, reading the remainders upwards. Neither is a black box, and this page refuses to be one.