Free Percentage Calculator Online | Increase, Decrease & More

It supports operations such as finding X% of Y, what percent X is of Y, percentage increase, percentage decrease, and percentage difference.

Yes. The percentage calculator is free to use, and all processing happens in your browser — your data is not stored or transmitted.

Percentage increase = ((New − Old) / Old) × 100. Percentage decrease = ((Old − New) / Old) × 100.

Percentage difference = |A − B| / ((A + B) / 2) × 100, useful when comparing two values regardless of order.

Basic Percentage

Percentage Increase

Percentage Decrease

Percentage Difference

What is % of ?

is what percent of ?

Increase by %

Decrease by %

What is the percentage change from to ?

🔑 Key Features & Benefits

Covers all key percentage operations: “X% of Y”, part-to-whole, increase, decrease, difference.
User-friendly interface — input values, pick operation, get instant result.
Accurate and precise calculations — reduces manual error.}
Works across devices — desktop, tablet, mobile.
Privacy-first — all calculation runs in browser; no data stored.
Useful for students, finance, business, shopping and everyday calculations.

What is a percentage calculator?
It’s a tool that helps you perform calculations like “what is X% of Y”, increase or decrease values by percentages, or compare two numbers in percentage terms.
How do I calculate percentage increase?
The formula is ((New − Old) / Old) × 100.
Can the result exceed 100%?
Yes — in cases of increase beyond original, percentage can be more than 100%.
Is this tool free?
Yes — the percentage calculator is completely free to use, without needing to sign up.
Is my data safe?
Yes — all inputs are processed locally in your browser; nothing is stored on servers.