How to Use Percentage Calculator

1

Select Calculation Type

Choose from: What is X% of Y? X is what percent of Y? or Percentage increase/decrease.

2

Enter Your Values

Input the numbers in the provided fields. Use decimal points for precision (e.g., 12.5).

3

Get Instant Result

Answer appears automatically as you type. No need to click calculate button.

4

Copy or Calculate Again

Use the result in your work, or adjust numbers for different scenarios instantly.

📐 Common Percentage Formulas
  • Find X% of Y: Y × (X/100) - What is 20% of 150? → 150 × 0.20 = 30
  • X is what % of Y: (X/Y) × 100 - 30 is what % of 150? → (30/150) × 100 = 20%
  • % Increase: ((New-Old)/Old) × 100 - Price rose from $50 to $60 → 20% increase

Frequently Asked Questions

How do I calculate percentage increase?
Subtract original from new, divide by original, multiply by 100. Example: $50 to $70 → (70-50)/50 × 100 = 40% increase. Our tool does this automatically.
Can I calculate what percentage one number is of another?
Yes! Use "X is what percent of Y" mode. Enter the part in X and whole in Y. Example: 25 is what % of 200? Answer: 12.5%
Does it handle negative percentages?
Yes! Negative results indicate decrease or loss. -15% means 15% decrease. Useful for calculating losses, discounts, or negative growth.
How to add percentage to a number (tax, tip)?
Use "What is X% of Y" to find the amount, then add to original. Or use our GST/Tip calculator for automatic total calculation including percentage.
Is there a limit on number size?
Handles up to 15-digit numbers accurately. For very large numbers (trillions+), results may show in scientific notation but remain precise.

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