Percentage Calculator
Three modes: X% of Y, percentage change, and what-percent.
Result
20% of 15030
Percentage Calculator — FAQs
How do I work out 20% of £150?
20 ÷ 100 × 150 = £30. Or multiply by 0.2.
Percentage change formula?
(new − old) ÷ old × 100. £80 → £100 is +25%; £100 → £80 is −20%.
How do I work out percentage increase?
(New − old) ÷ old × 100. £80 → £100 is a 25% increase.
How do I calculate percentage of a number?
Number × percentage ÷ 100 — 15% of 240 = 36.
What is the percentage difference?
|a − b| ÷ average × 100 — symmetric, unlike percent change which uses the original value.
How do I reverse a percentage?
Divide by (1 + p/100) to undo an increase, or (1 − p/100) for a decrease — £120 after 20% added was £100, not £96.
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