Percentage Calculator - Calculate Percentages Online Free

How to Use the Percentage Calculator

1. Choose a mode — select from “What is X% of Y?”, “X is what % of Y?”, or “What is the % change?”
2. Enter the values — fill in the two numbers in the corresponding fields
3. Get instant result — the answer appears as you type, with the formula shown
4. Copy the result — click to copy the calculated value to your clipboard
5. Switch modes — change calculation type without losing your entered values

All calculations run in your browser — no data is sent to any server.

Features

• Three modes — find the percentage of a number, find what percent one number is of another, or calculate percentage change
• Real-time updates — results change as you type, no button clicks needed
• Formula display — shows the math behind each calculation for learning and verification
• Copy results — one-click copy to clipboard
• Clean interface — distraction-free design focused on the calculation at hand
• 100% local — all processing in the browser

Use Cases

Shopping for discounts — quickly calculate 30% off a $79.99 item to see if it fits your budget. Enter “30” and “79.99” in the “What is X% of Y?” mode and get the savings amount and final price instantly.

Tracking grades — if you scored 85 out of 120 on an exam, use the “X is what % of Y?” mode to find your percentage score. Teachers also use this to calculate class averages and grade distributions.

Analyzing business metrics — revenue grew from $50,000 to $65,000. Use the “% change” mode to calculate a 30% increase. This mode is essential for quarterly reports, sales performance reviews, and growth analysis.

Calculating tips — dining out and want to leave an 18% tip on a $62.50 bill? The “What is X% of Y?” mode gives you $11.25 instantly.

FAQ

What is the difference between the three modes?

“What is X% of Y?” finds a portion of a number (e.g., 15% of 200 = 30). “X is what % of Y?” finds the percentage relationship (e.g., 30 is 15% of 200). “% change” finds the increase or decrease as a percentage (e.g., 50 to 75 is a 50% increase).

Can I calculate percentage increases?

Yes. The “% change” mode handles both increases and decreases. Enter the original value and the new value — the calculator shows the percentage difference and indicates whether it is a rise or fall.

Is this calculator accurate for decimal numbers?

Yes. The calculator handles decimal inputs and displays results with appropriate precision. For financial calculations, results are typically shown to two decimal places.

Do I need to sign up or create an account?

No. This tool is completely free and requires no registration. Just open the page and start calculating.

Can I use this offline?

Once the page has loaded, all calculation logic runs in your browser. The tool works without an internet connection.

Tips

• For reverse percentage calculations, use “X is what % of Y?” mode — it tells you the proportional relationship
• When calculating tips, use “What is X% of Y?” — 15% is standard, 18-20% for excellent service
• For investment returns, “% change” mode tells you the percentage gain or loss between two values