What is the Percentage Increase Calculator?
Use this percentage increase calculator to compare an original value with a new value and see the exact percent change. It also shows the raw difference, growth multiplier, and whether the result is an increase or decrease.
The calculator is useful for salary raises, price changes, revenue growth, traffic changes, grades, investment value changes, and everyday math. You can also solve the new value after a percentage change or find the original value before a change.
What is the Percentage Increase Calculator?
A percentage increase calculator measures how much one number has grown compared with its starting value. The main formula subtracts the original value from the new value, divides by the original value, and multiplies by 100.
This version also works as a percentage change calculator because a negative result is shown as a decrease. That makes it useful when you need one tool for increase, decrease, and before-and-after comparisons.
Percentage increase, decrease, and percent change explained
Percentage increase means the new value is higher than the original value. For example, moving from 100 to 125 is a 25 percent increase because the value grew by 25 compared with a starting value of 100.
Percentage decrease means the new value is lower than the original value. The same formula can show a negative percent change, which tells you the value went down rather than up.
Percent change is the broader term. It covers both increase and decrease, while raw difference shows the actual number of units gained or lost.
How to use the Percentage Increase Calculator
Choose the calculation mode that matches what you know. Use the two-value mode for normal before-and-after comparisons, or use the solve modes when you know the percent change and need the missing value.
- Choose percent change between two values when you know the original value and the new value.
- Enter the original value and the new value to calculate the percent increase or decrease.
- Choose find new value after percent change when you know the starting value and the percentage increase or decrease.
- Choose find original value before percent change when you know the final value and the percent change.
- Review the percent change, raw difference, multiplier, and formula steps in the result table.
How each input affects the result
Use this guide before filling the calculator. It explains what the main input areas mean, how to enter them, and how each one can change the estimate.
| Input area | What it means | Impact on result |
| Main value | The primary number requested by the calculator. | It drives the main result and should be entered carefully. |
| Rate, percentage, or adjustment | A percentage assumption used in the estimate. | Changing it can increase or decrease the final result. |
| Time period | The number of periods used in the calculation. | It affects totals, averages, and projections. |
| Optional fields | Extra assumptions used only when they apply. | Use 0 when an optional value does not apply so it does not affect the result. |
What your results mean
After calculating, start with the main result card, then use the detail rows to understand why the number changed. This makes it easier to compare scenarios without guessing.
| Result line | What it means |
| Main result | The primary estimate produced by the calculator. |
| Breakdown rows | Supporting values that explain how the result was created. |
| Comparison or schedule | Optional detail used to compare scenarios or review changes over time. |
Example
For example, if a price rises from 80 to 100, the difference is 20. Divide 20 by the original value of 80, then multiply by 100. The percentage increase is 25 percent.
Percentage increase formula
- Difference = new value minus original value
- New value after change = original value × (1 + percent change / 100)
- Original value before change = new value / (1 + percent change / 100)
- A positive percentage shows an increase and a negative percentage shows a decrease
Percentage change is not defined in the normal way when the original value is zero. Use the raw difference or compare from a non-zero starting value in that case.
Why use this calculator?
A percentage increase calculation can look simple, but mistakes happen when users divide by the new value instead of the original value. This calculator keeps the formula clear and shows the steps behind the result.
- Calculates percent increase and decrease from two values.
- Shows the raw difference as well as the percentage result.
- Solves the new value after a percentage increase or decrease.
- Solves the original value before a known percent change.
- Works for prices, salary, revenue, traffic, grades, and other everyday number changes.
- Adds a clear interpretation giving you a clearer view of whether the value increased or decreased.
Best for
- Students learning percent change formulas.
- Shoppers comparing price increases or sale changes.
- Workers checking salary raise percentages.
- Website owners comparing traffic, clicks, or impressions.
- Business users reviewing revenue, cost, or growth changes.
Pros and things to check
Potential benefits
- Fast result for two-number comparisons.
- Supports increase and decrease in one calculator.
- Shows formula steps for learning and verification.
- Useful for everyday math and basic business analysis.
Important checks
- Percent change from zero is not defined in the usual formula.
- Large percentage changes can look dramatic when the original value is very small.
- A percentage increase does not explain why the change happened.
Percentage increase result guide
Use this table to understand which calculation mode fits your situation.
| Need | Use this mode |
| Find growth from old to new value | Percent change between two values |
| Increase a number by a known percent | Find new value after percent change |
| Find the starting value before a percent increase | Find original value before percent change |
| Compare a drop instead of growth | Use a negative percent change or enter a lower new value |
| Original value is zero | Use raw difference because normal percent change is not defined from zero |
Percentage calculation note
Percentage calculations are general math estimates. Use exact records, invoices, pay statements, analytics data, or financial statements when the result affects a real decision.
FAQs
What is a percentage increase calculator?
It calculates how much a number increased compared with its original value. It can also show the raw difference and percentage change.
How do I calculate percentage increase?
Subtract the original value from the new value, divide the result by the original value, and multiply by 100.
Can this calculator show percentage decrease?
Yes. If the new value is lower than the original value, the percent change is negative and the calculator explains it as a decrease.
What is the difference between percentage increase and percent change?
Percentage increase focuses on growth. Percent change is broader because it can show either an increase or a decrease.
Can I calculate a salary increase percentage?
Yes. Enter the old salary as the original value and the new salary as the new value to estimate the raise percentage.
Can I calculate price increase percentage?
Yes. Enter the old price and new price to see the price increase percentage and the raw price difference.
How do I increase a number by a percentage?
Use the find new value mode. Enter the original value and the percentage change, then the calculator estimates the new value.
How do I find the original value before a percentage increase?
Use the find original value mode. Enter the final value and the percent change to estimate the starting value.
Why is percentage change from zero a problem?
The standard formula divides by the original value. Division by zero is not defined, so use the raw difference instead.
Is this calculator exact?
It applies standard percentage formulas to the values entered. Real-world records and rounding can still change the final number you use.
How do I use the Percentage Increase Calculator?
Enter the values requested by the calculator, review the result summary, then adjust one input at a time to compare different scenarios.
What result should I check first?
Start with the main result at the top of the calculator, then use the detail table or explanation to understand how the number was produced.
Can I enter zero in optional fields?
Yes. If a field is optional, entering 0 should keep it at 0 rather than replacing it with a hidden default value.
Why can the final result be different?
Real results can vary because of local rules, provider settings, tax treatment, timing, personal details, and data accuracy.
What information should I use?
Use the most recent records, statements, bills, documents, or estimates available so the result is as realistic as possible.
Can I compare more than one scenario?
Yes. Change one input at a time and compare how the result changes. This helps you understand which assumption matters most.