Calculators
Percentage Calculator
Calculate percentages, percentage change and discounted prices.
Runs in your browser · No file or text uploads
Preparing your tool…
What Percentage Calculator helps you do
Find part of a total, compare old and new values, or calculate a discount with the denominator made explicit.
How to use it
- Choose the calculation type.
- Enter the base value and percentage or comparison value.
- Calculate and check the substituted formula.
Input and output example
INPUT
Original price: 50 / Discount: 20%OUTPUT
Discount amount: 10 / Final price: 40
Supported formats and limits
- Currency is not assumed. This is not a tax or financial-advice calculator.
- The denominator cannot be zero for percentage share or change. Discounts must be 0–100%.
How the result is calculated
Share = part ÷ total × 100. Change = (new − old) ÷ old × 100. Discount amount = original × rate ÷ 100. Results are rounded to at most 6 decimal places.
Frequently asked questions
What is the increase from 100 to 120?
(120 − 100) ÷ 100 × 100 = 20%. The decrease from 120 to 100 has a different denominator and a different percentage.