How to Convert from Base 10 to Base 8

Converting numbers from base 10 (decimal) to base 8 (octal) might seem tricky at first, but it becomes straightforward with a bit of practice. Let’s break it down step-by-step.

Step-by-Step Process

  1. Divide the Number by 8
    Start by dividing the base 10 number by 8 and write down the quotient and the remainder. The remainder is the least significant digit (rightmost digit) of the base 8 number.

  1. Repeat the Division
    Take the quotient from the previous division and divide it by 8 again. Write down the new quotient and remainder. The remainder from this division is the next digit in the base 8 number.

  1. Continue Until the Quotient is Zero
    Keep repeating the division process until the quotient becomes zero. The remainders collected, read from bottom to top, give you the base 8 number.

Example

Let’s convert the decimal number 345 to base 8.

  1. First Division: 345 ÷ 8 = 43, remainder 1
  2. Second Division: 43 ÷ 8 = 5, remainder 3
  3. Third Division: 5 ÷ 8 = 0, remainder 5

Reading the remainders from bottom to top, we get the base 8 number: 531.

Another Example

Convert the decimal number 156 to base 8.

  1. First Division: 156 ÷ 8 = 19, remainder 4
  2. Second Division: 19 ÷ 8 = 2, remainder 3
  3. Third Division: 2 ÷ 8 = 0, remainder 2

Reading the remainders from bottom to top, we get the base 8 number: 234.

Verification

To verify, you can convert the base 8 number back to base 10. For example, let’s convert 531 (base 8) back to base 10:

$5 times 8^2 + 3 times 8^1 + 1 times 8^0 = 5 times 64 + 3 times 8 + 1 times 1 = 320 + 24 + 1 = 345$

This confirms that 345 in base 10 is indeed 531 in base 8.

Conclusion

Converting from base 10 to base 8 involves repeated division by 8 and collecting remainders. With practice, this method becomes second nature. Understanding this process is essential for various applications in computer science and digital electronics.

3. Wikipedia – Octal

Citations

  1. 1. Khan Academy – Number Systems
  2. 2. Math is Fun – Number Bases