Percentage Calculator – Calculate Percentages Online
Free online percentage calculator from ToolGuru. Calculate X% of Y, find what percent one number is of another, and measure percentage increase or decrease in your browser.
Calculation
🔒 Your calculations are performed in your browser and are not uploaded.
Free Percentage Calculator
Use this percent calculator for everyday questions: what is 20% of 150, 30 is what percent of 150, or how much 150 changed when it became 180. Calculations run in your browser.
How to Calculate a Percentage
A percentage of a number is the percent times the value, divided by 100. So 20% of 150 is 20 × 150 ÷ 100 = 30. To ask “what percent is X of Y?”, divide X by Y and multiply by 100: 30 ÷ 150 × 100 = 20%.
Percentage Increase and Decrease
Percentage change is (new − original) ÷ original × 100. From 150 to 180 that is a 20% increase. From 180 to 150 that is a 16.67% decrease. A zero original value cannot be used as a starting point for change.
How to Use This Calculator
Pick a calculation, enter the two numbers, and choose Calculate. Copy the result if you need it in a note or spreadsheet. Related: the Discount Calculator applies a percent off a price.
Privacy
Your calculations are performed in your browser and are not uploaded.
How to Use This Calculator
Step 1
Choose a calculation
Pick “What is X% of Y?”, “X is what percent of Y?”, or percentage change.
Step 2
Enter the numbers
Use whole numbers or decimals. Empty values and a zero total are rejected with a clear message.
Step 3
Calculate and copy
See the result, copy it, or clear the form to start again. Nothing is uploaded.
Frequently Asked Questions
How do I calculate a percentage of a number?
Choose “What is X% of Y?”, enter the percent and the value, then calculate. Example: 20% of 150 is 30.
How do I find what percent one number is of another?
Choose “X is what percent of Y?”, enter the part and the total. 30 is 20% of 150. If the total is zero, the calculator explains that a percentage cannot be found.
How is percentage change calculated?
Percentage change is (new − original) ÷ original × 100. 150 to 180 is a 20% increase. 180 to 150 is a 16.67% decrease.
Is the percentage calculator free?
Yes. Calculate percentages without an account or payment.
Are my numbers uploaded?
No. Your calculations are performed in your browser and are not uploaded.