Octal to Decimal Converter
Convert octal numbers to decimal.
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Convert octal to decimal
Enter an octal number, which uses only the digits 0 through 7, to read its decimal value, with reverse conversion included. Octal is base 8 and once appeared widely in computing; today it shows up most often in Unix file permissions, where each digit sets read, write and execute bits. The digits are validated before any output appears.
How it reads
The octal 52 is 5 times 8 plus 2, which equals 42 in decimal.
Frequently asked questions
What digits does octal use?
Octal uses 0 through 7 only. Each place value is a power of eight, rising as 1, 8, 64 and so on from right to left.
Where is octal still used?
Most commonly in Unix and Linux file permissions, where a value like 755 describes access rights as octal digits.