Percentage Calculator
A percentage calculator answers the three percentage questions that come up everywhere: what is X% of Y, X is what percent of Y, and how much has a value increased or decreased in percent. FreeToolsKit's calculator solves all three instantly and shows the formula behind each answer, so the result is never a black box.
Last updated: October 20, 2026
What is X% of Y?
50
(25 ÷ 100) × 200 = 50
X is what % of Y?
75%
(45 ÷ 60) × 100 = 75%
Percentage increase / decrease
+25%
((100 − 80) ÷ 80) × 100 = 25%
Key takeaways
- Three calculators in one page: percentage of a number, one number as a percent of another, and percentage change.
- Every answer shows the exact formula used, so you can verify or reuse the working.
- Percentage change is signed — a decrease shows as a negative percentage.
- Results update as you type; there is no calculate button to press.
How do you calculate a percentage?
- Find the card that matches your question — there are three, one per formula.
- Type the two numbers the question asks for.
- Read the answer, which appears instantly as you type.
- Check the formula line under the answer to see how it was worked out.
- Change any number and the answer updates immediately.
What is the Percentage Calculator used for?
- Working out a sale discount — what 25% off a price leaves you paying.
- Calculating a tip or a service charge as a percentage of a bill.
- Finding what score you achieved as a percentage on a test or exam.
- Measuring growth — how much sales, followers or savings rose between two periods.
- Checking a tax or VAT amount included in a total price.
Frequently asked questions
How do I calculate what percent X is of Y?
Divide X by Y and multiply by 100: (X ÷ Y) × 100. For example, 45 out of 60 is (45 ÷ 60) × 100 = 75%. The second calculator on this page does exactly this.
How is percentage increase calculated?
Subtract the old value from the new value, divide by the old value, and multiply by 100: ((new − old) ÷ old) × 100. A positive result is an increase; a negative result is a decrease.
What is the difference between percent and percentage points?
Percent is relative; percentage points are the plain difference between two percentages. A rise from 4% to 5% is a 25% relative increase, but only 1 percentage point. This calculator's change mode reports the relative percent.
Why does a 50% loss need a 100% gain to recover?
Because the base changes. Losing 50% of 100 leaves 50; gaining 50% of 50 adds only 25. To get back to 100 you need to double 50 — a 100% gain. Percentages always apply to the current value, not the original.
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