Davemi ToolsPercentage Calculator
Calculate percentages, increases, and decreases — instantly.
What is X% of Y?
% of=40
X is what % of Y?
is what % of=20%
Percentage increase/decrease
Fromto=+20%
Frequently Asked Questions
How is percentage increase/decrease calculated?
It's the difference between the two values, divided by the original value, expressed as a percentage — a positive result means an increase, negative means a decrease.
Is my data uploaded anywhere?
No. All calculations run locally in your browser — nothing is sent to a server.
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