Free Online Tool

Convert Octal to Hexadecimal

Need to convert an octal number to hex? Our free octal to hexadecimal converter makes it easy. Simply enter your base-8 value (using digits 0-7) to get the base-16 result instantly. No manual math required!

Octal to hexadecimal calculator

Allowed digits: 0 through 7
Output digits: 0–9 and A–F
Enter a value above to see the result
Conversion Octal (Base 8) → Hexadecimal (Base 16)

Octal to Hex Conversion Chart

Skip the manual math with this quick reference guide. Here are the most common octal to hex conversions, completely calculated for you.

Common octal to hexadecimal conversions from 0 to 7777
Octal Calculation (Decimal equivalent) Hexadecimal
0 0 0
1 1 1
7 7 7
10 8 8
17 15 F
20 16 10
25 21 15
37 31 1F
40 32 20
77 63 3F
100 64 40
177 127 7F
200 128 80
377 255 FF
777 511 1FF
1000 512 200
7777 4095 FFF

How to Convert Octal to Hexadecimal

Wondering how to convert octal into hexadecimal by hand? The easiest method is to use binary as a stepping stone.

The Conversion Method

Since octal is a base-8 number system (using digits 0-7) and hexadecimal is a base-16 system (using digits 0-9 and letters A-F), a direct conversion is tricky. Instead, translate the octal number to binary first, then convert that binary number into hex.

Octal → Binary → Hexadecimal

Because each octal digit translates cleanly into 3 binary bits, and each hexadecimal digit translates into 4 binary bits, regrouping the 0s and 1s makes the math simple.

How to Change Octal to Hexa

1

Write the octal number

Start with the octal value you want to calculate. Let's look at a popular convert octal to hexadecimal example: 157.

2

Convert each octal digit to binary

Map the digits: 1 is 001, 5 is 101, and 7 is 111. Smush them together to get 001101111 in binary.

3

Group the binary into 4-bit sets

Starting from the right, group the binary digits into fours: 0110 and 1111. (You can ignore any leftover zeros on the far left).

4

Translate the groups to hexadecimal

Now look at your 4-bit groups. 0110 equals 6, and 1111 equals F. Therefore, 157₈ converts to 6F₁₆.

Understanding Octal to Hex Conversion

Why do we need an octal hexadecimal converter? While octal and hexadecimal are both positional number systems heavily used in computer programming, they serve slightly different functions.

Historically, early computing relied on octal because 3-bit binary groups were common in older architectures. Today, hexadecimal is the standard for web colors, memory addresses, and machine code because it condenses 4 binary bits into a single, highly readable character.

If you want to learn how to do an octal to hexadecimal conversion, the manual step-by-step regrouping method is a great exercise. But for everyday work, using a dedicated octal to hexadecimal calculator saves time and prevents basic arithmetic errors.

Octal to Hexadecimal Examples

Looking for an octal to hexadecimal example? Here is how the math breaks down for some popular values.

10 in octal to hexadecimal

An octal 10 equals an 8 in standard decimal. In hex, an 8 is simply an 8. So 10₈ = 8₁₆.

17 in octal to hexadecimal

The octal number 17 represents 15 in decimal. In base-16, a 15 is represented by the letter F. That means 17₈ = F₁₆.

20 in octal to hex

An octal 20 converts to 16 in decimal. Because hex uses a base-16 system, that rolls over to 10. So 20₈ = 10₁₆.

37 in octal to hexa

Octal 37 is 31 in decimal. In hex, this becomes 1F. So 37₈ = 1F₁₆.

157 in octal to hexadecimal

As shown in our step-by-step method, 157 equals 111 in decimal. In hex, this translates to 6F.

377 in octal to hexadecimal

The octal number 377 is a very common maximum value. It equals 255 in decimal, which is the highest 8-bit value. This converts perfectly to FF in hexadecimal.

777 in octal to hex

An octal 777 translates to 511 in decimal. When converted to base-16, this becomes 1FF.

1000 in octal to hexadecimal

Octal 1000 equals 512 in decimal. In hex, this is represented as 200.


Frequently Asked Questions

Everything you need to know about navigating our convert octal to hex tool.