Convert an Octal Number to Decimal Number

The same number can be written in any base. Decimal uses base-10 digits 0-9; Octal uses base-8 digits 0-7. Converting between them is a change of notation, not of value - and when computers favour one base while human eyes favour another, Octal-to-Decimal conversion becomes a daily habit.

Convert an Octal Number to Decimal Number Converter reads any octal number and writes the identical value in decimal. BigInt keeps every conversion exact at any size, batches run up to 1000 values per click, and the list copies or downloads one line each.

• Exact BigInt: Every conversion exact at any size.
• Base-10 output: Clean decimal digit strings.
• Input validation: Invalid octal flagged per line.
• Batch mode: Up to 1000 conversions at once.
• Readable digits: Decimal output as typed.
• Copy or download: Export all results.

1. Enter octal numbers - one per line, digits 0-7 only.
2. Generate - BigInt conversion runs on every line.
3. Read the decimal results - each paired with its input.
4. Copy or download - the converted list.

1. 12, 377, 2000, 144: converted to Decimal as 12 -> 12; 377 -> 377; 2000 -> 2000; 144 -> 144 - every row exact.

2. 12: the same quantity written in base 10, the decimal answer.

3. Zero and one: 0 and 1 map to 0 and 1 in every base - the universal anchors.

4. A large value: feed a long octal string and BigInt keeps every digit of the decimal result exact.

5. Batch: paste several octal values and each row returns its own decimal form.

• Notation, not maths: The value never changes - only its spelling.
• Zero loss: BigInt keeps huge octal inputs exact.
• Batch friendly: Hundreds of conversions per run.
• Self-validating: Bad octal digits flagged per line.
• Copy or download: Results export in one click.
• Private and free: Everything runs in the browser; nothing is uploaded or logged.