Tiny Toolkit

Percentage Calculator

Switch between three percentage modes: find what X% of a number is, calculate what percentage one number is of another, or compute the percentage increase or decrease between two values. Results update instantly as you type. A quick go-to for discounts, tips, grade calculations, and everyday math.

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Frequently Asked Questions

What are the three types of percentage calculations?
1) Finding X% of Y (e.g. 20% of 150 = 30). 2) Finding what percentage X is of Y (e.g. 30 is 20% of 150). 3) Calculating the percentage increase or decrease from one value to another.
How is percentage change calculated?
Percentage change = ((new value − old value) / |old value|) × 100. A positive result means an increase; a negative result means a decrease.
Can I calculate a percentage decrease?
Yes — use the '% change' mode and enter the higher value in 'From' and the lower value in 'To'. The result will be a negative percentage showing the decrease.

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