How this calculator works
An octal position carries a power of eight. To encode decimal, divide repeatedly by eight and read the remainders backwards. To decode, multiply every digit by its power of eight and add. The tool treats the input as a plain unsigned integer without decimal points, signs or prefixes, and retains exact digits up to the supported bit limit.
Formula
Decimal = sum(d_i x 8^i). For encoding, N = 8q + r with 0 <= r <= 7; collect r from successive divisions.
Worked example
Decimal 64 is 1 x 8², so its octal form is 100. Octal 755 decodes as 7 x 64 + 5 x 8 + 5 = 493.
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Frequently asked questions
Can an octal value include a decimal point?
This integer converter does not accept fractional octal. Every entered digit must be 0 through 7.
Is a leading zero required?
No. A leading zero is a programming convention in some languages, not part of the arithmetic.
Will a very large integer lose digits?
The conversion uses integer arithmetic. Values exceeding 4096 significant bits are rejected explicitly.