Percentage Calculator
Pick the kind of percentage question you have — a share of a number, a comparison between two numbers, or a change over time — and get the answer instantly.
Overview
"Percentage" questions come in a few distinct shapes that use different formulas, which is why a single generic calculator often isn't enough. This tool covers the three most common ones: finding a percentage of a number, working out what percentage one number represents of another, and calculating the percentage increase or decrease between two values.
Examples
X% of a number
20% of 150
30
What percent
30 is what % of 150
20%
Percentage change
From 100 to 120
20% increase
How It Works
- Pick a calculation mode: X% of a number, what percent one number is of another, or percentage change.
- Enter the two numbers the selected mode needs.
- The result appears instantly as you enter the values.
FAQ
No. Every calculation runs locally in your browser.
(New value − Old value) ÷ Old value × 100. A positive result is an increase, a negative result is a decrease.
Yes, for the percentage change calculation. "X% of a number" and "what percent" expect non-negative values for meaningful results.
Percentage change is a relative change (e.g. 20 increasing to 25 is a 25% change). Percentage points is the raw arithmetic difference between two percentages (e.g. going from 20% to 25% is a 5 percentage point increase) — this calculator computes percentage change, not points.