What digits are valid in octal?

Only 0–7. Any digit 8 or 9 makes the input invalid.

Can I enter a leading zero?

Yes, e.g. 077 is valid octal and equals 63 in decimal.

This tool accepts non-negative octal strings only.

Convert an octal (base 8) number to decimal.

Octal number (digits 0–7)

What digits are valid in octal?: Only 0–7. Any digit 8 or 9 makes the input invalid.
Can I enter a leading zero?: Yes, e.g. 077 is valid octal and equals 63 in decimal.
What about negative octal?: This tool accepts non-negative octal strings only.

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