Octal to Decimal Converter
Convert octal numbers to decimal. Octal values from Unix permissions and older systems are converted to decimal when they must be compared with ordinary numbers.
Octal to Decimal converter
Result
- Binary
- —
- Octal
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- Decimal
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- Hexadecimal
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How to convert octal to decimal
Multiply each octal digit by 8 raised to the power of its position, counting from 0 at the right, then add the results.
Example: 234 (octal) to decimal
234 = 2 × 8² + 3 × 8¹ + 4 × 8⁰
= 128 + 24 + 4 = 156
Examples
- 12 (octal) = 10 (decimal)
- 234 (octal) = 156 (decimal)
- 377 (octal) = 255 (decimal)
- 1750 (octal) = 1000 (decimal)
Octal to Decimal conversion table
| Octal (base 8) | Decimal (base 10) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 2 |
| 3 | 3 |
| 4 | 4 |
| 5 | 5 |
| 6 | 6 |
| 7 | 7 |
| 10 | 8 |
| 11 | 9 |
| 12 | 10 |
| 13 | 11 |
| 14 | 12 |
| 15 | 13 |
| 16 | 14 |
| 17 | 15 |
| 20 | 16 |
| 24 | 20 |
| 40 | 32 |
| 62 | 50 |
| 100 | 64 |
| 144 | 100 |
| 177 | 127 |
| 200 | 128 |
| 377 | 255 |
| 400 | 256 |
| 1000 | 512 |
| 1750 | 1000 |
| 2000 | 1024 |
The table lists the same whole numbers for every pair of bases.
Frequently asked questions
- What is 377 in decimal?
- 377 in octal is 255 in decimal.
- How do I convert octal to decimal by hand?
- Multiply each octal digit by 8 raised to the power of its position, counting from 0 at the right, then add the results.
- What digits does octal use?
- Octal uses the digits 0 to 7. Octal is best known from Unix file permissions: chmod 755 is three octal digits, one for owner, group and others.
- What is decimal used for?
- Decimal is the everyday number system for counting, money and measurement.