Our free percentage calculator handles the four most common percentage problems people encounter in everyday life — all in one convenient tool. Whether you need to find a percentage of a number, calculate what percent one number is of another, find the percentage change between two values, or apply a percentage increase or decrease, this calculator delivers instant results.

Percentages appear constantly in everyday life — from sale discounts and tax calculations to test scores and investment returns. Having a reliable percentage calculator at hand makes all of these calculations effortless and error-free.

How to Use the Percentage Calculator

This percentage calculator has four independent calculation modules — use whichever one fits your need:

1. What is X% of Y? — Enter a percentage and a value to find the result. For example, 15% of 200 = 30.
2. X is what % of Y? — Enter two numbers to find what percentage the first is of the second.
3. Percentage Change — Enter original and new values to find the percentage increase or decrease.
4. Percentage Increase/Decrease — Enter a value and a percentage to find the new amount after the change.

When Should You Use a Percentage Calculator?

Use the percentage calculator whenever you encounter a percentage problem in daily life. For instance, use it when calculating a restaurant tip, working out a sale discount, figuring out your grade on a test, or understanding an investment return. In addition, it is invaluable for business owners who need to calculate profit margins or markup percentages.

Furthermore, the percentage change calculator is particularly useful for comparing statistics, data, or financial figures over time. For example, if a stock went from $50 to $65, the percentage change tool instantly tells you that is a 30% increase.

Percentage Formulas You Should Know

Here are the fundamental percentage formulas for quick reference:

• Finding a percentage: Result = (Percentage / 100) × Total. Example: 20% of 150 = (20/100) × 150 = 30.
• What percent is X of Y? Percentage = (X / Y) × 100. Example: 30 is what % of 150? = (30/150) × 100 = 20%.
• Percentage increase: New Value = Original × (1 + Rate/100). Example: 200 increased by 15% = 200 × 1.15 = 230.
• Percentage decrease: New Value = Original × (1 – Rate/100). Example: 200 decreased by 15% = 200 × 0.85 = 170.
• Percentage change: Change% = ((New – Old) / |Old|) × 100.

Frequently Asked Questions About the Percentage Calculator

How do I calculate a tip using percentages?

To calculate a 20% tip on a $75 bill: $75 × 0.20 = $15 tip, making the total $90. For 15%: $75 × 0.15 = $11.25 tip. Our percentage calculator handles this instantly.

How do I calculate a discount?

To find the sale price after a 30% discount on a $120 item: $120 × (1 – 0.30) = $120 × 0.70 = $84. Alternatively, find 30% of $120 = $36, then subtract from $120.

Related Calculators

Furthermore, you might find these related tools useful: Scientific Calculator — Fraction Calculator