Hexadecimal to Octal

Convert hexadecimal numbers to octal. Useful for cross-referencing between different number systems in programming.

What is the Hexadecimal to Octal Converter?

This tool converts hexadecimal numbers (base-16) to octal numbers (base-8). Both are power-of-2 systems widely used in computing.

How it works: the value is converted through binary or decimal as an intermediate step, since 16 = 2⁴ and 8 = 2³.

Why Convert Hex to Octal?

Multiple Formats

Different tools and platforms use different number systems.

Cross-Referencing

Compare hex addresses against their octal equivalents.

Learning Number Systems

See how the bases relate through their shared binary roots.

The Conversion Method

Convert via decimal (hex → decimal → octal), or via binary since both are power-of-2 bases.

Example: FF (hex) = 255 (dec) = 377 (oct).

How to Use

Enter the Hex Number

Type the digits 0–9 and the letters A–F.

View the Octal Result

The conversion happens instantly in the second field.

Copy the Result

Copy the octal value wherever you need it.

Bidirectional: both fields are editable. Type an octal value in the result field to convert it back to hexadecimal, or use the swap button to flip the direction.

Common Values

Hex	Octal	Decimal
`A`	12	10
`FF`	377	255
`100`	400	256

Frequently Asked Questions

Can hex convert directly to octal?

There is no direct digit-to-digit mapping because 16 and 8 do not align cleanly. The conversion goes through binary or decimal as an intermediate step.

Why is FF equal to 377 in octal?

FF is 255 in decimal. In octal, 377 = 3×64 + 7×8 + 7×1 = 192 + 56 + 7 = 255 — the maximum value of one byte.

When would I need this conversion?

It is handy when comparing documentation or tools that mix formats — for example, reading a hex address while a Unix utility reports the same value in octal.