Percentage Calculator
Compute percentages, discounts, markups, and percentage increases or decreases in real time.
1. What is X% of Y?
2. X is what percent of Y?
3. Percentage change (from X to Y)
4. Discount or markup on a price
How to use the Percentage Calculator
Our online percentage calculator brings together the four most common percentage formulas used in everyday shopping, invoicing, finance, and schoolwork. Results update automatically as you type, with no need to press a submit button.
Use Card 1 to find a direct percentage of any value, Card 2 to see what share one number represents of another, Card 3 to measure percentage growth or decline between two periods, and Card 4 to quickly apply retail discounts or add sales tax.
Usage example
Scenario: You are buying an item priced at $120 with a 25% discount.
Result: Using Card 4 ("Subtract 25% from 120"), you save $30 and pay a final price of $90.
Frequently Asked Questions
How do you calculate the percentage of a number?
Multiply the total number by the percentage you want to find, then divide by 100. For instance, 15% of 200 is (200 × 15) / 100 = 30.
How do you calculate percentage change between two numbers?
Subtract the starting value from the ending value, divide by the absolute starting value, and multiply by 100: ((Final − Initial) / |Initial|) × 100. A positive result indicates an increase, while a negative result indicates a decrease.
How do I apply a discount or add sales tax to a price?
In the fourth calculator card, enter your base amount, choose "Subtract" for a discount or "Add" for tax/markup, and type the percentage. Both the final amount and the difference are shown immediately.