Percentage Calculator
Free percentage calculator with four modes: X% of Y, X is what % of Y, percentage change, and increase/decrease by %. Fast and accurate.
Why Use a Percentage Calculator?
Percentage calculations come up constantly in everyday life and business — calculating discounts, tips, tax amounts, growth rates, and more. Our calculator provides four essential percentage operations in one tool, so you don't need to remember formulas or do mental math. Just enter your values and get instant results.
Key Features
- Four calculation modes for different percentage needs
- Percentage change with increase/decrease indication
- Simultaneous increase and decrease results
How to Use
- Select the calculation mode you need from the tabs
- Enter the values in the input fields
- View the result instantly and copy if needed
Technical Details
The four percentage calculations are: (1) X% of Y = (X/100) × Y, (2) X is what % of Y = (X/Y) × 100, (3) % change = ((new-old)/|old|) × 100, (4) Increase = base × (1 + pct/100), Decrease = base × (1 - pct/100). All calculations are performed client-side with floating-point arithmetic.
FAQ
How do I calculate a percentage increase?
Use the '± %' tab. Enter the base value and the percentage. The tool shows both the increased and decreased values.
What's the difference between percentage change and increase by %?
Percentage change calculates how much a value changed relative to the original. 'Increase by %' adds a percentage to a base value.
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