Octal to HEX

Octal to HEX

Use our tool to change a number written in base 8 (octal) to a number written in base 16 (hexadecimal). We'll show you the steps and formulas we use to do this conversion.

In the world of computing and digital electronics, different number systems are used to simplify various processes. Two of the most commonly used systems are the octal (base-8) and hexadecimal (base-16) systems. Understanding how to convert between these systems is crucial for programmers, engineers, and students alike. In this article, we'll explore everything you need to know about converting octal to hexadecimal, including the basics of each number system, the conversion process, and practical applications.

Understanding Number Systems

Before diving into the conversion process, it's important to understand the basics of the octal and hexadecimal number systems.

What is the Octal Number System?

The octal number system is a base-8 numeral system that uses the digits 0 through 7. Each digit in an octal number represents a power of 8. Octal numbers are commonly used in computing, especially in older systems and applications where binary representation was cumbersome.

Example of an Octal Number:

  • 1758

In this example, the digits from right to left represent:

  • 8^: 5
  • 8^: 7
  • 8^: 1

What is the Hexadecimal Number System?

The hexadecimal number system, or hex, is a base-16 numeral system that uses sixteen distinct symbols: 0-9 to represent values zero to nine and A-F to represent values ten to fifteen. Hexadecimal numbers are widely used in computer science and digital electronics because they can represent binary numbers more succinctly.

Example of a Hexadecimal Number:

  • 1AF

In this example, the digits from right to left represent:

  • 16^: F (15 in decimal)
  • 16^: A (10 in decimal)
  • 16^: 1

Why Convert Octal to Hexadecimal?

Conversion between octal and hexadecimal is often required in various fields, including:

  • Computer Programming: Different programming languages and systems may require numbers to be represented in different bases.
  • Digital Electronics: Circuit designers and engineers often work with different number systems for ease of calculation and representation.
  • Education: Students learning about computer architecture and number systems often need to convert between various bases.

Steps to Convert Octal to Hexadecimal

The process of converting an octal number to a hexadecimal number involves two main steps: converting the octal number to a binary number, and then converting the binary number to a hexadecimal number.

Step 1: Convert Octal to Binary

Each octal digit can be represented by a 3-bit binary equivalent. This is because 2^3=8, so three binary digits are sufficient to represent any octal digit.

Octal to Binary Conversion Table:

Octal Digit Binary Equivalent
0 000
1 001
2 010
3 011
4 100
5 101
6 110
7 111

Example Conversion:

  • Octal Number: 175

Convert each octal digit to its binary equivalent:

  • 1: 001
  • 7: 111
  • 5: 101

Combine the binary equivalents:

  • 1758=0011111012

Step 2: Convert Binary to Hexadecimal

Each group of four binary digits (bits) can be represented by a single hexadecimal digit. If the number of bits is not a multiple of four, pad the binary number with leading zeros.

Binary to Hexadecimal Conversion Table:

Binary Group Hexadecimal Digit
0000 0
0001 1
0010 2
0011 3
0100 4
0101 5
0110 6
0111 7
1000 8
1001 9
1010 A
1011 B
1100 C
1101 D
1110 E
1111 F

Example Conversion:

  • Binary Number: 001111101

Pad the binary number to make a multiple of four bits:

  • 000111110101

Convert each group of four bits to a hexadecimal digit:

  • 0001: 1
  • 1111: F
  • 0101: 5

Combine the hexadecimal digits:

  • 1758=1F516

Practical Applications

Computer Programming

Programmers often need to work with different number systems. For example, when dealing with low-level programming or hardware design, hexadecimal numbers are preferred for their compact representation. Converting from octal to hexadecimal can help in debugging and understanding code, especially when working with machine-level instructions.

Digital Electronics

In digital electronics, different bases are used to simplify the design and analysis of circuits. Hexadecimal is particularly useful in microcontroller programming and digital signal processing. Converting octal to hexadecimal can streamline the interpretation of data sheets and memory addresses.

Educational Purposes

Learning about different number systems and their conversions is a fundamental part of computer science and engineering education. Understanding these concepts helps students grasp the underlying principles of digital logic and computer architecture.

Tools for Conversion

Online Converters

Several online tools can help you convert octal to hexadecimal quickly and accurately. These tools are useful for quick checks and learning purposes.

Calculator Functions

Many scientific calculators have built-in functions to convert between different bases. These can be especially handy for students and professionals working offline.

Programming Languages

Most programming languages, such as Python, provide built-in functions to convert between different number systems. Here's an example in Python:

# Convert Octal to Hexadecimal in Python

# Function to convert octal to hexadecimal
def octal_to_hex(octal):
    # Convert octal to decimal
    decimal = int(octal, 8)
    # Convert decimal to hexadecimal
    hexadecimal = hex(decimal)
    return hexadecimal

# Example usage
octal_number = '175'
hexadecimal_number = octal_to_hex(octal_number)
print(f"Octal: {octal_number} -> Hexadecimal: {hexadecimal_number[2:].upper()}")

This script converts an octal number to a hexadecimal number by first converting the octal number to a decimal and then converting the decimal number to hexadecimal.


Converting octal to hexadecimal is a fundamental skill in computing and digital electronics. Understanding the conversion process helps in various applications, from programming to circuit design. By following the steps outlined in this guide, you can easily convert octal numbers to their hexadecimal equivalents. Whether you're a student, a professional, or just someone interested in number systems, mastering this conversion will enhance your computational skills and broaden your understanding of digital systems.

Remember, practice makes perfect. Use the provided examples, tools, and techniques to become proficient in converting between octal and hexadecimal systems. Happy converting!


Azahar Ahmed

CEO / Co-Founder

I am Azahar Ahmed, a youthful Engineer, Entrepreneur, Digital Marketer, and Motivational speaker native to Nagaon, Assam, India. Originating from a middle-class background, I am the sole son. My accomplishments are indebted to my father, a Teacher, and my mother, formerly a Teacher but now devoted to our well-being. My mother has been my closest ally, and unitedly, my parents have fostered and realized all my aspirations, epitomizing the perfect parents.

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