**Octal Subtraction Calculator** is an online tool used in digital computation to perform subtraction between two octal numbers. In digital circuits, the octal arithmetic operations are for humans to easily understand the arithmetic operation but the digital circuit operates only on binary numbers 0's and 1's. Octal numbers are the numbers ranges from 0 to 7 and its base is represented by 8. To perform the subtraction, enter the two octal numbers into each respective place given in this octal subtraction calculator and click on the calculate button generates the resulting output. The decimal equivalent output is also shown in this calculator's output to confirm the result