Check before acting
- Name the base value before entering a percentage.
- Do not treat equal percentage decreases and increases as mathematical reversals.
- Keep unrounded values when the result feeds a later tax, fee or finance calculation.
EVERYDAY WORKBENCH · NEW
Percentage Calculator
Solve percentage, change, discount and reverse-percentage questions with the formula shown clearly.
01
Choose the question
Switch modes without losing your values.
percentage ÷ 100 × baseDECISION GUIDE
How to use this result in a real decision.
Which number is the base, and is the task a share, a change, a discount or a reverse calculation? The same two numbers can answer different questions. Select the relationship first, keep the base visible and round only the displayed result rather than intermediate values.
WORKED EXAMPLE
A 20% discount on $250
- Inputs
- 20% discount and a $250 original price.
- Calculated result
- The discount amount is $50 and the price after discount is $200.
- Decision meaning
- A later 20% increase on $200 adds $40, producing $240—not the original $250—because the second percentage uses a smaller base.
Not included automatically
- Taxes, fees or compounding not represented in the selected mode
- Statistical significance and the business meaning of a percentage change
- Rules for financial, medical or regulatory reporting
Every result exposes the assumptions behind it.
Inputs are calculated in this browser and are not uploaded.
Copy the result or save a clean PDF report.