Convert Hexadecimal to Octal
Need a fast hex to octal conversion? Enter any base-16 number (using digits 0–9 and letters A–F) into our free hex to octal calculator below to instantly get its base-8 value. We'll also show you the exact steps on how to convert from hex to octal yourself.
Hex to octal converter
Quick Reference
Hexadecimal to Octal Conversion Table
Here is a quick look at common hexadecimal to octal conversions. Keep this handy if you want to convert hex to octal quickly without opening an app.
| Hexadecimal | Calculation | Octal |
|---|---|---|
| 0 | 0 | 0 |
| 1 | 1 | 1 |
| 7 | 7 | 7 |
| 8 | 8 | 10 |
| A | 10 | 12 |
| F | 15 | 17 |
| 10 | 1×16¹ + 0×16⁰ = 16 | 20 |
| 1A | 1×16¹ + 10×16⁰ = 26 | 32 |
| 2F | 2×16¹ + 15×16⁰ = 47 | 57 |
| 3C | 3×16¹ + 12×16⁰ = 60 | 74 |
| 7B | 7×16¹ + 11×16⁰ = 123 | 173 |
| 80 | 8×16¹ = 128 | 200 |
| 9D | 9×16¹ + 13×16⁰ = 157 | 235 |
| FF | 15×16¹ + 15×16⁰ = 255 | 377 |
| 100 | 1×16² = 256 | 400 |
Step-by-Step
How to Convert Hexadecimal to Octal
Wondering exactly how to convert from hexadecimal to octal by hand? A direct translation is tough, so the easiest method is to use binary code as a temporary bridge.
The Method
Hexadecimal is a base-16 number system, while octal is a base-8 system. The simplest way to convert hex to octal is to translate the hex number into binary first, and then group those binary digits to form your new octal number.
Because hex translates perfectly into 4-bit blocks, and octal relies on 3-bit blocks, you just swap the grouping to find your answer.
How to Change Hexadecimal to Octal
Write the hexadecimal number
Take the hex value you want to calculate. Let's use 1A3 as our example.
Convert hexa to binary
Turn each character into 4-bit binary. 1 = 0001, A = 1010, 3 = 0011. Combined, you get 0001 1010 0011.
Regroup the binary into 3s
Start from the far right and group the digits by threes: 000 110 100 011.
Convert each group to octal
Now, read the 3-bit blocks. 000 = 0, 110 = 6, 100 = 4, 011 = 3. Put them together, and you've found that 1A3₁₆ = 643₈.
Hex vs Octal
Understanding Hexadecimal a Octal Conversions
Both hexadecimal and octal serve as shorthand for binary code, making long sequences of 0s and 1s easier for humans to read.
While hexadecimal (base 16) is highly popular in modern computing (like assigning HTML color codes or memory addresses), octal (base 8) is still widely used in systems like Linux to quickly assign file permissions.
Instead of doing the math manually every time, you can use our convert hex to octal calculator to speed up your workflow and avoid mistakes.
Worked Examples
Sample Hex to Octal Conversions
Here is how to convert from hex to octal for some of the most frequently searched values.
A in hex to octal
The letter A in hex is 10 in decimal. When you translate that to base-8, you get 12. So, A₁₆ = 12₈.
F in hex to octal
The letter F equals 15 in decimal. When mapped out, you get 17. So, F₁₆ = 17₈.
10 in hex to octal
The value 10 in hexadecimal equals 16 in standard decimal. Translated to octal, this is 20. So, 10₁₆ = 20₈.
1A in hex to octal
Converting 1A gives us 26 in decimal, which equals 32 in octal. So, 1A₁₆ = 32₈.
2F in hex to octal
2F corresponds to 47 in decimal. In octal, that translates to 57. So, 2F₁₆ = 57₈.
7B in hex to octal
7B converts to 123 in decimal. When mapped to base-8, you get 173. So, 7B₁₆ = 173₈.
FF in hex to octal
FF is a very common hex value that equals 255 in decimal. Translated to octal, you get exactly 377. So, FF₁₆ = 377₈.
FAQ
Frequently Asked Questions
Quick answers for anyone looking to convert hexadecimal to octal.