Percentage Calculator

Fast percent math: X% of Y, what percent is A of B, percent change, and increase/decrease.

1) What is X% of Y?

Formula: Y × (X / 100)

2) A is what percent of B?

Formula: (A / B) × 100

3) Percent change (from Old to New)

Formula: ((New − Old) / Old) × 100

4) Increase / decrease by X%

Formula: Base × (1 + X/100)
Tip
You can type decimals with a dot (.) or comma (,). Negative percentages work too.
🧮 Percent math ⚡ Instant 📱 Mobile-friendly
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Common questions

“What is 15% of 240?” “How much did it increase from 120 to 150?” “25 is what percent of 200?” Use sections 1–4 above depending on the question.

15% of 240 → 36 120 → 150 → 25% 25 of 200 → 12.5%