Increase or decrease a starting value. Available with Premium in The Percentage Calculator app.
A monthly plan or lifetime Premium purchase is required for this feature.
Use the app’s increase or decrease mode when you already know the percentage and need the resulting value. These modes require Premium. The free percentage change tool finds an unknown rate between two known values.
Select the direction that matches the change you want to apply.
For a 15% increase on 200, the increase is 30 and the new value is 230. A 15% decrease from 200 leaves 170.
Apply each later rate to the updated amount. An increase and decrease of the same percentage do not cancel each other.
Store listings: App Store and Google Play. Check your store for compatibility and current purchase options.
To increase a value by p%, multiply it by (1 + p/100). For a decrease, use (1 − p/100). This applies a known rate to a starting amount.
Percentage change solves a different question: it finds the unknown rate between two known amounts. Applying a known rate and finding an unknown rate use different inputs.
To calculate an increase, find the given percentage of the starting amount, then add it to the original value. A 20% increase on 150 adds 30 and gives 180. Subtracting 20% removes 30 and leaves 120.
| Operation | Multiplier | Example |
|---|---|---|
| Add 5% | 1.05 | 200 × 1.05 = 210 |
| Add 20% | 1.20 | 150 × 1.20 = 180 |
| Subtract 5% | 0.95 | 200 × 0.95 = 190 |
| Subtract 15% | 0.85 | 80 × 0.85 = 68 |
| Subtract 100% | 0 | 80 × 0 = 0 |
Applying 10% twice gives a combined increase of 21%, because 100 becomes 110 and then 121. Each increase applies to the current amount.
A 20% markup on a cost of 100 produces a selling price of 120. The profit margin on that selling price is 20 ÷ 120 × 100, or about 16.67%. Markup and margin use different denominators, so the same numeric percentage does not describe both.
To undo a known increase or decrease, use the reverse percentage method. For a rate between two known amounts, use the free percentage change calculator.
No. Starting at 100, a 20% increase gives 120. Reducing 120 by 20% leaves 96 because the second calculation uses a different base.
Use the increase or decrease mode with Premium in the app. This page contains fixed examples; four other percentage modes are free online and in the app.
Only when the starting amount is 100. On 250, a 10% increase adds 25 and gives 275. Adding a fixed 10 gives 260.
Subtract the decimal rate from 1. To subtract 12.5%, multiply by 1 − 0.125 = 0.875. Applied to 80, the result is 70.
