Reverse percentage calculator
Find the original number before a percentage increase or decrease.
How this calculator works
Original = final ÷ (1 + p) for an increase, or final ÷ (1 − p) for a decrease. Taking the percentage off the final value gives the wrong answer.
Worked example: a price of $132 after a 10% rise was originally $120, not $118.80. This is also how you take GST out of a price (÷ 1.1).
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