％ Percentage calculator with step-by-step working
Add or subtract a percentage, find a percentage of a number, work out what percent one number is of another, or measure percent change — each with the steps shown. Handy for GST, discounts, margins and price changes.
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How do I add GST (18%) to a price?
Choose “Add a % to a number”, enter the price and 18. The result is price × 1.18.
How do I calculate percent change?
Subtract the old value from the new value, divide by the old value, and multiply by 100.
How do I find what percent X is of Y?
Divide X by Y and multiply by 100.