Percentage Increase Calculator

How to calculate percentage increase

The percentage increase between any two numbers is the size of the change divided by where it started:

percentage increase = (ending value − starting value) ÷ |starting value| × 100

Three steps, using the page defaults:

1. Find the change: 75 − 50 = 25
2. Divide by the starting value: 25 ÷ 50 = 0.50
3. Convert to a percent: 0.50 × 100 = 50%

If the ending value is smaller, the same formula returns a negative result — 75 → 50 gives −33.33%, displayed as a decrease. If nothing changed, it returns 0%. The one case with no answer is a starting value of 0: 0 → 25 is "something from nothing", and there is no percentage for it (you would be dividing by zero). This calculator says "Not defined" rather than printing infinity.

You'll also see a ratio line: 75 ÷ 50 = 1.5, so the ending value is 150% of the original. That is the multiplier form — useful when you want to apply the same jump somewhere else.

Why an increase and a decrease never cancel out

Because the denominator changes. A 25% raise takes $120,000 → $150,000, but falling back to the start from $150,000 is only a 20% cut — the identical $30,000 is now being compared to a bigger number. The higher the increase, the more lopsided the pair becomes:

So "+20% then −20%" is not a round trip, whatever a retailer's sale sticker implies. Start at $250, add 20% to reach $300, then take 20% off and you're at $240 — a 4% loss overall, not a wash. The same rule is why stacked increases beat the sum of their parts: two consecutive 10% increases don't make 20%, they make 21% (1.1 × 1.1 = 1.21). Give that effect enough time and it compounds hard — see the compound interest calculator for what repeated growth does over decades.

Percentage increase in everyday money

Every row above divides the change by the left column, never the right one — that single choice is where most manual math goes wrong. And a raise only partly survives taxes and withholding; the income tax calculator shows what actually lands in your take-home pay.

Percent vs. percentage points

They sound alike and mean different things. If a rate rises from 3% to 4%, that's a rise of 1 percentage point (simple subtraction: 4 − 3) but a 33.33% increase (the formula above: 1 ÷ 3). Use percentage points when comparing two rates — interest rates, unemployment, survey shares — and percent increase when describing how much a single quantity grew.

Mistakes worth checking twice

• Dividing by the ending value. A $300,000 sale that cost $240,000 is a 25% gain, not a 20% one. The denominator is always the starting value.
• Adding percentages. Three 5% increases are 15.76%, not 15%. Multiply the multipliers: 1.05 × 1.05 × 1.05 = 1.1576.
• Averaging percentages across different bases. A 50% gain on $10 and a 10% gain on $1,000 are not "30% on average".
• Rounding mid-calculation. Keep full precision until the last step; rounding 33.333% to 33% and then reusing it can move a total by thousands.
• Comparing across currencies or units. Percentages are unit-free, which makes them easy to compare and equally easy to compare wrongly.

How to use this calculator

1. Pick the mode: find the % change (you have two numbers) or increase a number by a % (you have one number and a rate).
2. Enter the values. The defaults (50 → 75, or 20% on 250) are already filled in, so the page shows a result before you touch anything.
3. Read the main card — percentage change, the amount it represents, and what it takes to get back where you started.
4. Open the table below it for common percentages (5% through 100%) applied to your starting value, so you can eyeball the scale without re-typing.

Frequently asked questions

How do you calculate the percentage increase between two numbers?

Subtract the original number from the new one, divide by the original, and multiply by 100. Going from 50 to 75 gives (75 − 50) ÷ 50 × 100 = 50%. If the new number is smaller, the result is negative and you have a percentage decrease instead.

Is percentage increase the same as percentage difference?

No. Percentage increase divides by the starting value, so direction matters. Percentage difference usually divides by the average of the two values, which makes it symmetric — useful when comparing two measurements with no clear "before" and "after".

Why isn't a 50% increase cancelled by a 50% decrease?

The base changes in between. Starting at 100, +50% gives 150; losing 50% of 150 leaves 75 — a net 25% loss. To undo a +50% increase you need a −33.33% decrease, because the drop is measured against the larger number.

How do I increase a number by a percentage?

Multiply by (1 + rate as a decimal). Adding 20% to 250 is 250 × 1.20 = 300. Switch this calculator to "increase a number by a %" and it returns both the new value and the amount added.

Can a percentage increase be larger than 100%?

Yes. Anything that more than doubles has increased by over 100%: 50 → 120 is a 140% increase, and 50 → 150 is a 200% increase. Reducing something by more than 100%, however, is impossible — that would require going below zero.

What percentage increase did I get if my salary went from $60,000 to $63,750?

It's 6.25%: a $3,750 raise divided by your old salary of $60,000. Note that a raise is usually quoted on base pay, while the money you actually receive changes with withholding — check the effect on take-home pay before budgeting it.

How do I calculate a percentage increase over several years?

Don't add the yearly percentages. Multiply the yearly multipliers and subtract 1: gains of 10%, 20%, and 5% give 1.1 × 1.2 × 1.05 = 1.386, which is a 38.6% increase over the whole period, not 35%.

Data sources: The formula used here is the standard percentage change definition [(new − original) ÷ |original| × 100], the same one applied across this site's finance calculators. Every example on this page was computed by this page's own engine and can be reproduced exactly by loading it with the stated inputs (50 → 75 is the default, so you can check it without typing anything). No external or estimated figures were used. Related tools: compound interest calculator, income tax calculator, how much house can I afford, all finance calculators, all math calculators.