Octal ↔ Hex Converter
This free octal to hex converter translates values between base-8 and base-16 instantly. Both octal and hex are shorthand notations for binary, so conversions are exact and lossless, making this tool useful for legacy systems, file permissions, and low-level programming.
How to Convert Octal to Hex Manually
Octal is a base-8 system using the digits 0 through 7. Because 8 and 16 are both powers of two, the cleanest way to convert octal to hex is to pass through binary: expand each octal digit into three bits, regroup those bits into four-bit nibbles, and translate each nibble to hex.
For example, the octal value 377 expands to the binary 11111111. Grouped into nibbles that is 1111 1111, which becomes FF in hex. This octal to hex converter performs the whole pipeline instantly, whether your value is a few digits or very long.
- Convert each octal digit to its three-bit binary form.
- Combine the binary digits into one continuous string.
- Group the bits into sets of four, starting from the right.
- Translate each nibble to its hex symbol to get the result.
How to Convert Hex to Octal Manually
To convert hex to octal, work in reverse: expand each hex symbol into four binary bits, regroup the bits into groups of three starting from the right, and translate each group to an octal digit.
Take the hex value FF, which is 11111111 in binary. Grouped into threes from the right that is 11 111 111, padded to 011 111 111, giving octal 377. The converter above applies this logic automatically in both directions.
When Do You Need Octal and Hex?
Octal appears most often in Unix file permission notation and some older assembly code, while hex dominates modern debugging, memory addresses, and color values. Being able to move between them quickly helps when integrating legacy systems with modern tooling.
Bookmark this octal to hex converter for those moments when you need a fast, trustworthy translation without reaching for a calculator.