Octal to Decimal Converter
Free online octal to decimal converter with steps — instant, accurate octal to decimal conversion in your browser.
Supports arbitrarily large non-negative integers (BigInt under the hood).
About octal to decimal conversion
Number bases are just different ways of writing the same value: binary (base 2) uses digits 0–1, octal (base 8) uses 0–7, decimal (base 10) uses 0–9 and hexadecimal (base 16) uses 0–9 plus A–F. This converter parses your input as an arbitrary-precision integer and re-renders it in the target base — instantly and privately, in your browser.
Quick reference
1010in binary =12in octal =10in decimal =Ain hexadecimal- Hexadecimal digits:
A=10, B=11, C=12, D=13, E=14, F=15 - Each octal digit maps to exactly 3 binary digits; each hex digit maps to exactly 4
Frequently asked questions
How do I convert octal to decimal manually?
Multiply each octal digit by 8 raised to its position power (starting at 0 from the right) and add the results together.
What is octal 755 in decimal?
755 in octal equals 493 in decimal.
Is this converter free and private?
Yes — free, no sign-up, and the conversion runs locally in your browser using arbitrary-precision integers. Nothing is uploaded.