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).
Runs entirely in your browser — nothing you enter is uploaded or stored.
About octal to decimal conversion
Number bases are different ways of writing the same value: binary (base 2) uses 0–1, octal (base 8) 0–7, decimal (base 10) 0–9 and hexadecimal (base 16) 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
1010binary =12octal =10decimal =Ahex- Hexadecimal digits:
A=10, B=11, C=12, D=13, E=14, F=15 - Each octal digit maps to 3 binary digits; each hex digit maps to 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.