How to Calculate Percentage Increase
The formula, worked examples, common mistakes, and a free calculator. Covers price increases, salary raises, population growth, and more.
Last updated: April 2026
Percentage increase calculator
Enter the original value and the new value. The result is the percentage increase between them.
Find the new value after a percentage increase
Enter a starting value and a percentage increase to find the resulting value.
The percentage increase formula
To calculate the percentage increase between two values, you need to know the original (old) value and the new value. The formula is:
The logic is straightforward: you find the raw increase (New − Old), express that increase as a fraction of the original, then multiply by 100 to convert to a percentage. The result tells you how large the increase is relative to where you started.
Step-by-step worked example
Say a laptop cost $800 last year and now costs $960. Here is how to find the percentage increase:
Step 1 — Find the difference: New − Old = $960 − $800 = $160
Step 2 — Divide by the original: $160 ÷ $800 = 0.20
Step 3 — Multiply by 100: 0.20 × 100 = 20%
The laptop price increased by 20%.
You can verify this by working backwards: $800 × 1.20 = $960. The multiplier 1.20 represents the original 100% plus the 20% increase, all in a single multiplication.
Finding the new value after a percentage increase
If you know the original value and the percentage increase and want to find the result, use this formula:
For a 15% increase on $200: $200 × (1 + 15 ÷ 100) = $200 × 1.15 = $230. The “1 +” part ensures you keep the original amount; the fraction adds the increase on top. This is the calculation that powers the salary raise calculator — every raise percentage is simply applied as a multiplier to the current pay.
Real-world examples across common scenarios
The same formula works in every context where a value grows. Here are five typical use cases with full working:
| Scenario | Original | New value | Calculation | % Increase |
|---|---|---|---|---|
| Salary raise | $52,000 | $56,160 | (56,160 − 52,000) ÷ 52,000 × 100 | 8% |
| Product price | $24.99 | $27.49 | (27.49 − 24.99) ÷ 24.99 × 100 | 10% |
| Monthly revenue | $18,500 | $21,275 | (21,275 − 18,500) ÷ 18,500 × 100 | 15% |
| Website visitors | 4,200 | 5,460 | (5,460 − 4,200) ÷ 4,200 × 100 | 30% |
| House value | $340,000 | $374,000 | (374,000 − 340,000) ÷ 340,000 × 100 | 10% |
Notice that the formula is identical in every row. Whether you are comparing salaries, prices, traffic, or asset values, the arithmetic is always: subtract original from new, divide by original, multiply by 100.
Percentage increase vs percentage points — a critical distinction
These two phrases measure different things, and confusing them is one of the most common errors in financial and statistical communication. A percentage point is the simple arithmetic difference between two percentage values. A percentage increase measures the relative change from the starting value.
Suppose an interest rate rises from 2% to 3%. That is a 1 percentage point increase — the simple difference. But it is a 50% increase in the rate itself: ((3 − 2) ÷ 2) × 100 = 50%. Both statements are factually correct, but they describe different things. Advertisers and politicians frequently use whichever framing makes a change look smaller (or larger) for rhetorical effect. Understanding the distinction lets you evaluate claims accurately.
The same distinction matters when comparing things like inflation rates, tax rates, conversion rates, and survey results. The percentage change calculator always computes the relative percentage change — not the percentage point difference.
Can a percentage increase exceed 100%?
Yes, and this surprises many people. A 100% increase means the value exactly doubled (the increase equals the original). An increase above 100% means the value more than doubled. A 200% increase means the value tripled: an original of $50 growing by 200% becomes $50 + (200% of $50) = $50 + $100 = $150.
There is no upper mathematical limit. A startup valued at $1 million growing to $50 million has experienced a 4,900% increase. This is entirely valid arithmetic — it simply means the new value is 50 times the original.
Stacking percentage increases — they do not add up
A common mistake is to assume that a 10% increase followed by another 10% increase equals a 20% increase. It does not. The second percentage is applied to the already-increased value, not the original. Starting at $100: after the first 10% increase you have $110, and after a second 10% increase you have $121 — not $120. The combined effect is a 21% increase from the starting value.
This compounding effect matters enormously over time. Annual salary increases, investment returns, and price inflation all compound in exactly this way. Use the percentage change calculator to measure the overall increase between a starting and ending value whenever stacking is involved, rather than adding the percentages directly.
Quick mental math shortcuts
For common percentage increases, a few shortcuts make mental arithmetic faster. To find 10% of any value, move the decimal point one place to the left: 10% of $340 is $34. For 5%, halve the 10% figure: $17. For 20%, double the 10% figure: $68. For 25%, divide by four: $85. These building-block values can be combined to estimate any increase quickly before using a calculator to confirm.
When calculating a raise, for example, a quick check on a $48,000 salary with a 3% raise: 10% is $4,800, so 1% is $480, and 3% is $1,440. New salary: roughly $49,440. The salary raise calculator will give you the precise annual, monthly, and weekly figures.
How percentage increase relates to markup and profit margin
In business contexts, a percentage increase on cost is called a markup. A product that costs $40 to produce and sells for $60 has a 50% markup: ((60 − 40) ÷ 40) × 100 = 50%. This is identical to the percentage increase formula. What the markup formula does not tell you is the gross profit margin — the percentage of the selling price that is profit. For the same product, margin = (60 − 40) ÷ 60 × 100 = 33.3%. Markup is always calculated from cost (the original); margin is calculated from revenue (the new value). The markup calculator handles the markup calculation, and the profit margin calculator handles the margin conversion.
Percentage increase and percentage decrease are not symmetrical
If a value increases by 25% and then decreases by 25%, you do not end up where you started. Starting at 100: a 25% increase gives 125, and a 25% decrease on 125 gives 93.75 — a net loss of 6.25%. This asymmetry exists because each percentage is applied to a different base. The increase uses the original as the base; the decrease uses the higher value. Understanding this is essential when evaluating investment returns, price changes, or any sequence of up-and-down movements.