How to Convert Hexadecimal to Octal

Converting hexadecimal (hex) to octal directly involves two main steps because both numeral systems are powers of two (base-16 to base-8), which simplifies their interconversion. Unlike converting directly from hex to octal, a common approach involves an intermediary conversion through binary, which serves as a “universal donor” in numeral system conversions due to its base-2 simplicity.

Understanding the Systems

Conversion Process: Hex to Binary to Octal

Step 1: Convert Hex to Binary

  1. Break Down Hex Digits: Separate the hex number into individual digits.
  2. Convert Each Hex Digit to Binary: Use the standard conversion where each hex digit translates to a 4-bit binary number. The conversion is straightforward:
    • 0 = 0000
    • 1 = 0001
    • 2 = 0010
    • ...
    • A = 1010
    • ...
    • F = 1111
  3. Concatenate Binary Digits: Merge the 4-bit binary groups into a single binary sequence.

Step 2: Convert Binary to Octal

  1. Group Binary Digits into Sets of Three: Starting from the right, divide the binary sequence into groups of three. If the leftmost group contains fewer than three digits, pad it with zeros.
  2. Convert Each Binary Group to Octal: Each group of three binary digits translates to a single octal digit, from 000 = 0 to 111 = 7.
  3. Concatenate Octal Digits: Combine the octal values from step 2 to get the final octal number.

Example Conversion

Let’s convert the hexadecimal number 1A3 to octal:

Hex to Binary

  • 1 = 0001
  • A = 1010
  • 3 = 0011

Concatenate the binary digits: 000110100011

Binary to Octal

  • 000 = 0
  • 110 = 6
  • 100 = 4
  • 011 = 3

Therefore, the hexadecimal number 1A3 converts to the octal number 0643.

Conclusion

This conversion demonstrates the versatility and coherence of numeral systems in computer science, showcasing how different bases can represent the same numerical values in various contexts. The intermediate step through binary underscores binary’s foundational role in digital computing and the logical relationships between numeral systems. Mastering such conversions is essential for understanding data representation, manipulation in computing tasks, and the intricacies of computer architecture and software development.