Percentage Increase Calculator
Three calculation modes: find the percentage increase between two values, calculate a new value after a percentage increase or decrease, or work backwards to find the original value.
How to Use
- Find % Change tab: Enter an original value and a new value. The calculator tells you the percentage increase or decrease between them.
- Find New Value tab: Enter the original value and a percentage change (use a negative number for a decrease). The calculator computes the result after applying that change.
- Find Original Value tab: Enter the value after a percentage change was applied and the percentage that was applied. The calculator works backwards to find what the original was.
What You'll Discover
- Percentage change (Find % Change tab) — the increase or decrease from the original value to the new value, shown with a + or − sign. A positive result is a percentage increase; a negative result is a percentage decrease.
- New value (Find New Value tab) — the number you get after applying a percentage increase or decrease to the original.
- Original value (Find Original Value tab) — the starting number before a known percentage change was applied, worked out by reversing the change.
- Direction — a plain-language line such as "Increased by 25%" or "A 15% decrease was applied".
- Absolute change — the raw difference between the new and original values, in the same units as your inputs.
Results update as you type and are rounded to at most four decimal places. If the original value is zero, the percentage change is undefined (you cannot divide by zero), so the results stay blank. The same happens in the Find Original Value tab if you enter −100%, because no starting value can be reduced by 100% and still give a non-zero result.
Formulas
Find % Change:
% Change = ((New − Old) ÷ |Old|) × 100
Find New Value:
New Value = Original × (1 + % Change ÷ 100)
Find Original Value:
Original = New Value ÷ (1 + % Change ÷ 100)
The "Find Original" formula is especially useful when you know a price after tax or markup but need the pre-tax or pre-markup amount. For example, if a price is $120 after a 20% increase, the original is $120 ÷ 1.20 = $100.
Worked example: percentage increase step by step
A monthly rent goes from $1,500 to $1,620. What is the percentage increase?
- Subtract the original from the new value: $1,620 − $1,500 = $120.
- Divide by the original value: $120 ÷ $1,500 = 0.08.
- Multiply by 100: 0.08 × 100 = 8% increase.
The formula divides by the absolute value of the original, |Old|. For positive numbers this changes nothing. It only matters when the starting value is negative, such as a loss or a temperature below zero, where it keeps a "+" result meaning the value went up.
Examples
| Scenario | Original | Change | New Value | % Change |
|---|---|---|---|---|
| Salary increase | $50,000 | +10% | $55,000 | +10% |
| Discount applied | $200 | −15% | $170 | −15% |
| Price after 20% increase | $100 | +20% | $120 | +20% |
| Find original (paid $120 after 20% up) | $100 | +20% applied | $120 | — |
| Population growth | 5,000 | +8% | 5,400 | +8% |
Why Percentage Increases and Decreases Don't Cancel Out
A percentage is always taken of the value you start from. After a change, the starting value is different, so the same percentage no longer means the same amount. This is the most common source of mistakes with percentage increase.
Take a $40 stock that falls 25% to $30. To get back to $40 it must rise by $10 from $30, which is a 33.33% increase, not 25%. The drop and the recovery are the same $10, but they are measured against different bases.
Reversing an increase
To undo an increase of p%, you need a decrease of p ÷ (100 + p) × 100. The table shows common cases.
| Increase applied | Multiplier | Decrease needed to undo it |
|---|---|---|
| +10% | × 1.10 | −9.09% |
| +20% | × 1.20 | −16.67% |
| +25% | × 1.25 | −20% |
| +50% | × 1.50 | −33.33% |
| +100% (doubling) | × 2 | −50% |
Successive increases compound
Two 10% increases in a row are not a 20% increase. Each step multiplies by 1.10, so the total is 1.10 × 1.10 = 1.21, a 21% increase. To combine any series of changes, convert each to a multiplier (1 + p ÷ 100), multiply them together, then subtract 1 and multiply by 100.
The same logic explains why a 50% fall followed by a 50% rise leaves you at 75% of where you started: 0.5 × 1.5 = 0.75.
Percentage Increase vs Absolute Increase
An absolute increase is the raw difference, New − Old. A percentage increase scales that difference by the starting value. Both are useful, but they answer different questions.
Suppose two shops each gain 10 customers a week. One went from 2 to 12 customers, a 500% increase. The other went from 200 to 210, a 5% increase. The absolute change is identical; the percentage shows how big that change is relative to where each shop began. That is why growth rates, inflation and pay rises are usually quoted as percentages.
The flip side is that percentages from a tiny base can look dramatic. A jump from 2 to 12 sounds impressive as "500%", yet it is only 10 customers. When the starting value is small, report the absolute change alongside the percentage. The calculator shows both.
Percentage increase over several years
If a value grows from 100 to 150 over five years, the total increase is 50%. Dividing by five gives a simple average of 10% a year, but that overstates the yearly rate because growth compounds. The compound annual rate is (150 ÷ 100)1/5 − 1 ≈ 8.45% a year. Use the compound figure when comparing investments or prices over time.
Percentage increase in Excel or Google Sheets
With the old value in A2 and the new value in B2, enter =(B2-A2)/ABS(A2) and format the cell as a percentage. To increase a number by a percentage, use =A2*(1+C2), where C2 holds the percentage (for example 15%).
What Is the Percentage Increase If...
What is the percentage increase if a price goes from $80 to $100?
Going from $80 to $100 is a 25% increase. The price rose by $20, and $20 ÷ $80 × 100 = 25%. Note that the reverse, $100 down to $80, is only a 20% decrease, because that change is measured against $100.
What is the percentage increase if my salary goes from $52,000 to $55,000?
A raise from $52,000 to $55,000 is about a 5.77% increase. The raise is $3,000, and $3,000 ÷ $52,000 × 100 ≈ 5.77%. To see whether that beats inflation, compare it with the inflation rate for the same period.
What is the percentage increase if a value doubles?
Doubling is a 100% increase. If 40 becomes 80, the change is 40, and 40 ÷ 40 × 100 = 100%. A common mistake is to call doubling a 200% increase; 200% of the original is the new value, but the increase itself is 100%.
What is the percentage increase if a value triples?
Tripling is a 200% increase. If 40 becomes 120, the change is 80, and 80 ÷ 40 × 100 = 200%. In general, a value that becomes k times larger has increased by (k − 1) × 100%.
What is the percentage increase if rent goes from $1,500 to $1,620?
A rent rise from $1,500 to $1,620 is an 8% increase. The difference is $120, and $120 ÷ $1,500 × 100 = 8%. Over a year that adds $1,440 to your housing costs.
What is the percentage increase if the value falls from 250 to 200?
From 250 to 200 is a 20% decrease, shown as −20%. The change is −50, and −50 ÷ 250 × 100 = −20%. The calculator handles decreases with the same formula; the minus sign tells you the direction.
What is the percentage increase if a price rises 10% twice?
Two 10% increases add up to a 21% increase, not 20%. The second rise is applied to the already-higher price: 1.10 × 1.10 = 1.21. On a $100 item, the price goes to $110 and then to $121.
What is the percentage increase if a stock falls from $40 to $30 and then recovers?
The fall is −25%, but the recovery from $30 back to $40 is a 33.33% increase. Both moves are $10, yet the recovery is measured from the lower $30 base: $10 ÷ $30 × 100 ≈ 33.33%. Losses always need a larger percentage gain to recover.
What is the percentage increase if the original value is zero?
A percentage increase from zero is undefined. The formula divides by the original value, and dividing by zero has no answer. Going from 0 to 50 is an absolute increase of 50, so report it that way instead (for example, "sales went from 0 to 50 units").
What is the percentage increase if the starting value is negative?
A loss shrinking from −200 to −150 is a +25% change. The value rose by 50, and 50 ÷ |−200| × 100 = 25%. Dividing by the absolute value keeps the sign meaningful: positive means the number went up, even when both numbers are below zero.
People Also Search For
How to calculate percentage increase by hand
Subtract the original value from the new value, divide by the original value, and multiply by 100. For 64 to 80: 80 − 64 = 16, 16 ÷ 64 = 0.25, and 0.25 × 100 = 25%. If the answer is negative, it is a percentage decrease.
How to add a percentage to a number
Multiply the number by 1 plus the percentage written as a decimal. To add 15% to 240, multiply by 1.15: 240 × 1.15 = 276. This is what the Find New Value tab does. For a decrease, enter a negative percentage, so −15% multiplies by 0.85.
How to calculate percentage decrease
Use the same formula: (new − old) ÷ old × 100, and read the minus sign as a decrease. From 80 to 64 the change is −16, and −16 ÷ 80 × 100 = −20%. The gap is the same 16 as in the 64-to-80 example above, but the percentage differs because the base is 80, not 64.
How to find the original price before a percentage increase
Divide the final price by 1 plus the percentage as a decimal. If an item costs $138 after a 15% increase, the original was $138 ÷ 1.15 = $120. Do not subtract 15% of $138; that gives $117.30, which is wrong because the 15% was taken of $120.
Percentage increase formula in Excel
Use =(B2-A2)/ABS(A2) and format the cell as a percentage. A2 holds the old value and B2 the new value. Without percentage formatting, Excel shows the result as a decimal, such as 0.25 for 25%.
How to calculate the average annual percentage increase
Take the ratio of the final to the starting value, raise it to the power of 1 ÷ years, subtract 1, and multiply by 100. For growth from 100 to 150 over 5 years: (1.5)1/5 − 1 ≈ 0.0845, or about 8.45% a year. This compound rate is lower than the simple average of 10% because each year's growth builds on the last.
Frequently Asked Questions
What is the difference between percentage increase and percentage decrease?
A percentage increase means the new value is larger than the original (positive % change). A percentage decrease means the new value is smaller (negative % change). Both are calculated with the same formula: ((New − Old) / |Old|) × 100. The sign of the result tells you the direction.
Why can't I just reverse a 20% increase with a 20% decrease?
Because the percentage applies to different base values. A 20% increase on $100 gives $120. A 20% decrease of $120 is $96, not $100. To reverse a 20% increase you need to decrease by 16.67% (100 / 120 − 1). The "Find Original Value" tab in this calculator handles this automatically.
How do I find the original price before a percentage markup?
Use the "Find Original Value" tab. Enter the final price (after markup) as the new value and the markup percentage as the applied % change. For example, if a product sells for $150 after a 25% markup: Original = $150 ÷ 1.25 = $120. This is the standard wholesale-to-retail reverse calculation used in pricing and accounting.
Can percentage change exceed 100%?
Yes. A 100% increase means the new value is double the original. A 200% increase means the new value is triple. For example, if sales grow from $50,000 to $200,000, that is a 300% increase (the new value is four times the original). Percentage increases above 100% are common in fast-growing businesses, investments, and viral content metrics.
How is percentage increase used in finance?
Percentage increase and decrease are core to financial analysis. Year-over-year revenue growth, stock price returns, interest rate changes, and inflation calculations all use the percentage change formula. Analysts use it to compare performance across periods of different size, making percentage change far more informative than raw dollar differences when comparing companies or portfolios of different scales.
Is percentage increase the same as percentage change?
Percentage increase is percentage change when the result is positive. Percentage change is the general term and can be positive (an increase) or negative (a decrease). This calculator uses the same formula for both and shows the sign so you can tell them apart.
What happens if the original value is zero?
The percentage increase is undefined, because the formula divides by the original value and you cannot divide by zero. The results stay blank in that case. Describe the change in absolute terms instead, for example "from 0 to 50".
What is the difference between a percentage increase and a percentage point increase?
A percentage point increase is the simple difference between two percentages, while a percentage increase is relative to the starting value. If an interest rate rises from 4% to 5%, that is a 1 percentage point increase but a 25% increase in the rate. Use the Percentage Point Calculator when both of your values are already percentages.
How do I add two percentage increases together?
Multiply them rather than adding them. Convert each increase to a multiplier (for example, 10% becomes 1.10 and 5% becomes 1.05), multiply the multipliers, then subtract 1 and multiply by 100. A 10% increase followed by a 5% increase is 1.10 × 1.05 = 1.155, a total increase of 15.5%.
How many decimal places does the calculator show?
Results are rounded to at most four decimal places, and trailing zeros are dropped, so a clean answer like 25% shows as 25% rather than 25.0000%. For reports, round the final figure to the precision your data supports, typically one or two decimal places.
Is my data stored or sent anywhere?
No. All calculations run in your browser. Nothing you type is sent to a server or saved, and no account is needed.
Last reviewed: November 2026 — formulas and worked examples verified.