Percentage Calculator
Calculate X% of Y, percentage change, or percentage difference.
Parameters & Inputs
Calculated Breakdown
No calculation yet
Set your values on the left and click Calculate to view instantaneous results.
About Percentage Calculator
Percentage Calculator answers the three questions people actually have: what is X% of Y, X is what percent of Y, and what is the percentage change from X to Y.
It shows the formula alongside the result, so you can check the number instead of trusting a black box.
How to use Percentage Calculator
- 1
Pick a mode
Choose percent-of, percent-change, or share-of.
- 2
Enter the values
Results update as you type, with the formula shown underneath.
- 3
Copy the result
Copy the value or the worked formula for a document.
Questions about Percentage Calculator
How is percentage change calculated?
(new − old) / old × 100. A move from 200 to 250 is +25%.
Why is a 20% drop not undone by a 20% rise?
Because the second percentage applies to a smaller base. 100 → 80 → 96, not 100.
Does it round the result?
It shows two decimals by default; the exact value is kept internally.
Can I use negative numbers?
Yes, the formulas hold for negative values, including percentage change.
Related tools
Last updated November 2026. Files are processed on FilePlume's own hardware and deleted within 60 minutes; nothing is used for training.