General
Percentage Increase Calculator
Works a percentage increase, where the base is the original value.
Result
Percentage increase is always measured against the original value. Reversing the two numbers does not give the same percentage back. A rise from 100 to 150 is +50%, but the fall from 150 to 100 is −33%.
Get a Free Business AuditHow the calculation works
The change divided by the original value, multiplied by a hundred. The original value is the base, which means the same absolute increase represents a larger percentage from a smaller starting point, and that is why percentage changes from a small base can be enormous and uninformative.
What moves the number
- The original value as the base.
- Size of the absolute change.
- Whether the increase compounds over multiple periods.
- Whether the base itself is reliable.
Where this one goes wrong
A percentage increase from a very small base produces a large number that says little, which is why absolute figures belong alongside percentages whenever the base is small. Show both. Successive increases also compound rather than add, so two consecutive 10% increases produce 21% rather than 20%, which matters over several periods.
Before you quote
- Show the absolute figures alongside the percentage.
- Use the original value as the base, not the new one.
- Compound successive increases rather than adding them.
Questions
About this calculator
Do two 10% increases make 20%?
No, they make 21%, because the second applies to the already-increased figure. Successive percentage changes compound rather than add, and over several periods the gap between the two becomes substantial.
Why can a percentage increase be misleading?
Because a small base produces a large percentage from a small absolute change. A figure doubling from two to four is a 100% increase and barely matters, which is why absolute numbers belong alongside the percentage.
Which value is the base?
The original one. Dividing the change by the new value instead produces a smaller percentage and is the most common error in this calculation, particularly when working backwards from a known result.
The formula
(new − original) ÷ original × 100 = % increase
Put this calculator on your site
Free to embed. Paste this where you want it to appear. It stays up to date automatically because it loads from BDEVY.
Please keep the attribution line. It is the only thing we ask in return.
How to use this calculator
- Original value. Enter your own figure; the page starts at 1,200.
- New value. Enter your own figure; the page starts at 1,500.
- Or apply an increase of (%). Enter your own figure; the page starts at 10%.
The result updates as you type, so you can try a figure, see what it does to percentage increase, and change it back. Nothing you enter is sent anywhere or saved.
A worked example
These are the figures the calculator opens with. Every number in the results column below is produced by the same calculation the page runs, so you can follow it through before putting your own figures in.
What goes in
| Input | Value |
|---|---|
| Original value | 1,200 |
| New value | 1,500 |
| Or apply an increase of | 10% |
What comes out
| Result | Value |
|---|---|
| Percentage increase main result | 25.00% |
| Absolute change | 300 |
| Original increased by that % | 1,320 |
| Multiplier | 1.25 |
Going from 1200 to 1500 is an increase of 25.00%.
How sensitive the answer is
Holding everything else steady and changing only original value, this is what happens to percentage increase. It is worth knowing which of your inputs the answer actually hinges on, and which barely move it.
| Original value | Percentage increase |
|---|---|
| 600 | 150.00% |
| 900 | 66.67% |
| 1,200 example above | 25.00% |
| 1,800 | -16.67% |
| 2,400 | -37.50% |
Every other input is held at the example value while this one changes, which is not how a real job behaves. Treat it as a guide to which number matters most, not as five separate quotes.
What each figure means
- Original value
- A number, starting at 1,200.
- New value
- A number, starting at 1,500.
- Or apply an increase of (%)
- A percentage, between 0 and 1000, starting at 10%.
What the results tell you
| Result | What it is |
|---|---|
| Percentage increase | The headline result. A percentage. |
| Absolute change | A number. |
| Original increased by that % | A number. |
| Multiplier | A number. |
Keep going
Related calculators
Percentage Decrease Calculator
Works a percentage decrease, where reversing it needs a different percentage.
Open calculatorPercentage Calculator
Works percentages, where the base and the wording decide the answer.
Open calculatorRevenue Growth Calculator
Works revenue growth, where the compound rate and the period-on-period rate differ.
Open calculatorRunning a business, not just a calculation?
BDEVY is one partner for the marketing, websites, systems and automation behind a growing business. Start with a free audit of what you have now.