Octal โ Decimal Converter
Convert between octal and decimal number systems instantly
๐ Octal โ Decimal Conversion Details
Octal to Decimal Formula
Multiply each digit by its corresponding power of 8 and sum them up.
Decimal to Octal Formula
Read remainders in reverse
Repeatedly divide by 8 and collect remainders from bottom to top.
Bidirectional Conversion
This converter works both ways simultaneously:
- Type octal โ decimal updates automatically
- Type decimal โ octal updates automatically
- No buttons to click - works as you type
Common Uses
- Computer science education
- Digital electronics
- File permissions (Unix/Linux)
- Programming and debugging
๐ How This Converter Works
This is a bidirectional converter that works in real-time:
- Octal โ Decimal: When you type in the octal field, the decimal field automatically updates
- Decimal โ Octal: When you type in the decimal field, the octal field automatically updates
- No swapping needed: Both conversions happen simultaneously
- Real-time validation: Invalid octal digits (8-9) are automatically filtered
= (1 ร 8ยฒ) + (4 ร 8ยน) + (4 ร 8โฐ)
= (1 ร 64) + (4 ร 8) + (4 ร 1)
= 64 + 32 + 4
= 100โโ
// Decimal to Octal Example: 100โโ
100 รท 8 = 12 remainder 4
12 รท 8 = 1 remainder 4
1 รท 8 = 0 remainder 1
Read remainders from bottom: 144โ
๐ Conversion Table
| Octal | Decimal | Binary | Hexadecimal |
|---|---|---|---|
| 10โ | 8 | 1000โ | 8โโ |
| 20โ | 16 | 10000โ | 10โโ |
| 50โ | 40 | 101000โ | 28โโ |
| 100โ | 64 | 1000000โ | 40โโ |
| 144โ | 100 | 1100100โ | 64โโ |
| 377โ | 255 | 11111111โ | FFโโ |
โ Frequently Asked Questions
A: Octal is a base-8 number system that uses digits 0 through 7. It's commonly used in computing because it groups binary digits (bits) in sets of three.
A: Both input fields work simultaneously. When you change the octal value, decimal updates automatically. When you change the decimal value, octal updates automatically.
A: The converter automatically filters out invalid digits (8 and 9). Only digits 0-7 are accepted in the octal field.
A: Octal is used because it's easier to read than binary and directly corresponds to groups of 3 bits. It's also used for Unix/Linux file permissions.