What is the Octal to Binary Converter?
This tool converts octal numbers (base-8) to binary numbers (base-2). Each octal digit maps directly to exactly 3 binary bits.
Why Convert Octal to Binary?
Understanding Permissions
Legacy Systems
Learning Number Systems
The Conversion Method
Each octal digit converts to exactly 3 binary digits, so replace each digit with its 3-bit group.
755 = 111 101 101 = 111101101.How to Use
Enter the Octal Number
Type using the digits 0–7 only.
View the Binary Result
Each octal digit becomes 3 bits, and the conversion is instant.
Copy the Result
Copy the binary value to use in your work.
Unix Permission Example
| Octal | Binary | Permission |
|---|---|---|
| 7 | 111 | read + write + execute |
| 5 | 101 | read + execute |
| 4 | 100 | read only |
Frequently Asked Questions
Why does each octal digit become 3 bits?
Because 8 = 2³. A single octal digit can hold 8 values (0–7), exactly the range of 3 binary bits.
Can I enter 8 or 9?
No. Octal is base-8 and only allows the digits 0 through 7. The digits 8 and 9 are not valid.
How does this clarify chmod?
Expanding 755 to 111 101 101 shows the three permission triplets directly: rwx for owner, r-x for group, r-x for others.
Is the conversion always exact?
Yes. Each octal digit always produces exactly 3 binary bits, so the mapping is predictable with no rounding or ambiguity.
No comments yet. Be the first to comment!