Percentage Increase Calculator
Find the percent increase or decrease between two numbers
โฌ๏ธ Enter your values
Last updated June 2026
Method: Uses the standard percentage-change formula, ((new − old) ÷ |old|) × 100, with the original value as the base. Positive results are labeled an increase, negative results a decrease.
Included: Percent increase or decrease, the absolute difference, the growth multiplier, and a step-by-step breakdown of the calculation.
Not included: Compounding over multiple periods, percentage points vs. percent, and cases where the original value is zero (undefined). Results are exact arithmetic, rounded for display.
Percentage increase calculator: how it works
Suppose a price rises from 120 to 150. The change is 150 − 120 = 30, and dividing that by the original 120 gives 0.25, or a 25% increase. That is the core of what this percentage increase calculator does: it compares a new value to an original value and tells you how much it grew (or shrank) in percentage terms, plus the raw difference between them.
The percentage increase formula
Percentage change is always measured relative to the starting (original) value:
Percent change = ((New − Old) ÷ |Old|) × 100 If the result is positive, the value increased; if it is negative, it decreased by that amount. The absolute value in the denominator keeps the percentage meaningful even when the original number is negative, while the sign of the numerator still tells you the direction of the change.
Worked example, step by step
Say revenue grows from $8,000 to $10,000:
- Step 1 - difference: 10,000 − 8,000 = 2,000.
- Step 2 - divide by the original: 2,000 ÷ 8,000 = 0.25.
- Step 3 - multiply by 100: 0.25 × 100 = 25% increase.
Notice the absolute difference ($2,000) and the percentage (25%) tell two different stories: the dollar amount shows scale, while the percentage shows relative growth. A small business adding $2,000 grew 25%, but the same $2,000 added to $8,000,000 in revenue is a rounding error of 0.025%.
Increase vs. decrease vs. percentage points
A negative result is a percentage decrease: going from 200 to 150 is a 25% decrease. Be careful not to confuse a percent change with percentage points. If an interest rate rises from 4% to 5%, that is a 1 percentage-point change but a 25% increase. The two are not interchangeable, and mixing them up is one of the most common reporting errors.
Why increases and decreases are not symmetric
A 25% increase followed by a 25% decrease does not bring you back to where you started. Starting at 100, a 25% increase gives 125; a 25% decrease from 125 is 125 − 31.25 = 93.75 - lower than the original. This happens because each percentage is calculated against a different base. To reverse a 25% increase exactly, you need a decrease of 20% (25 ÷ 125). This calculator always uses the original value as the base, so the result answers exactly "how much did it change from the start?"
How to use this calculator
The tool needs just two numbers and works in a few seconds:
- Enter the original (old) value. This is your starting point - last year's revenue, the original price, the first measurement, whatever you are comparing from.
- Enter the new value. This is the figure you want to compare against the original - the current price, this year's total, the latest reading.
- Read the result. The calculator shows the percentage change (labeled increase or decrease), the absolute difference between the two numbers, and the growth multiplier so you can see the relationship at a glance.
- Check the step-by-step breakdown. It writes out the subtraction, the division by the original, and the multiplication by 100, so you can verify the math or learn the method.
You can enter decimals and negative numbers. The only value the calculator cannot accept is an original of zero, because percentage change is undefined when there is no base to grow from.
More worked examples
The same formula handles increases, decreases, and large jumps. A few quick scenarios:
- A pay raise: a salary going from $52,000 to $57,200 is (57,200 − 52,000) ÷ 52,000 × 100 = a 10% increase, or $5,200 more per year.
- A price drop: a jacket marked down from $80 to $60 is (60 − 80) ÷ 80 × 100 = −25%, a 25% decrease, saving $20.
- Website traffic doubling: visits rising from 4,000 to 8,000 is a 100% increase - the value exactly doubled.
- A tiny base, big jump: a follower count going from 25 to 400 is a 1,500% increase, because the gain of 375 is fifteen times the starting 25.
In every case the absolute difference tells you the scale and the percentage tells you the relative size of the change. Reporting both gives the fullest picture.
Where percentage increase is used in real life
Percentage change is one of the most widely used comparisons in everyday math and reporting because it puts changes of different sizes on the same scale:
- Personal finance: measuring a pay raise, a rent hike, the growth of a savings balance, or the return on an investment over a period.
- Shopping: checking how much a sale price was marked up or down, or comparing the change between two listed prices.
- Business and sales: tracking revenue, units sold, conversion rates, or costs from one quarter or year to the next.
- Health and fitness: describing a change in weight, blood pressure, or a personal record relative to a previous reading.
- School and statistics: reporting changes in test scores, populations, survey results, or any measured quantity over time.
Whenever you hear a figure described as "up 12%" or "down 8% year over year," that number was produced by the exact calculation this tool performs.
Key terms explained
- Original (old) value: the starting number you are comparing from. It is the denominator in the formula - the base that the change is measured against.
- New value: the number you are comparing to. The difference between it and the original drives the percentage.
- Absolute difference: the raw amount of the change (new − old), expressed in the same units as the values, not as a percentage.
- Percentage change: the difference expressed as a fraction of the original, multiplied by 100. Positive means increase, negative means decrease.
- Growth multiplier: the factor the original is multiplied by to reach the new value. A 25% increase has a multiplier of 1.25; a 25% decrease has a multiplier of 0.75.
- Percentage point: the simple arithmetic difference between two percentages. Distinct from percent change - moving from 4% to 5% is one percentage point but a 25% increase.
Percentage increase vs. compound growth
This calculator measures a single change between two points - the total increase from start to finish. It does not assume the change happened evenly over several periods. If you need the average growth per period across multiple steps, that is a different (compounding) calculation. For example, a value that grows from 100 to 200 over five years is a 100% total increase, but the average annual growth rate is about 14.9% per year, found by taking the fifth root of 2. Use a single percentage increase when you care about the overall change, and a compound growth rate when you need the steady rate that would produce it.
Tips for reporting percentage changes accurately
The arithmetic is simple, but how you present a percentage change decides whether your audience reads it correctly. A few practices keep the numbers honest:
- State the base period explicitly. "Sales rose 12%" means little without saying compared to what - last month, last quarter, or the same period a year ago. Year-over-year and month-over-month comparisons can tell very different stories.
- Distinguish "percent" from "percentage points." If a metric moves from 4% to 5%, say "up one percentage point" or "up 25%" - never just "up 5%," which is ambiguous and usually read the wrong way.
- Pair large percentages with the raw numbers. A 300% increase on a base of three units (3 to 12) is technically accurate but sounds far more dramatic than it is. The absolute figures restore proportion.
- Round consistently. Decide on the number of decimal places up front and apply it across every figure in a report so readers can compare them fairly.
- Mind the direction words. "A 25% decrease" and "75% of the original" describe the same end value but feel different; choose the framing that fits what you want to emphasize, and stay consistent.
Following these habits turns a correct calculation into a clear one - which matters as much as the math itself when the figure ends up in a budget, a headline, or a school assignment.
How to calculate percentage increase in Excel or Google Sheets
The same formula drops straight into a spreadsheet, which is the fastest way to apply it to a whole column of values. Put the original value in cell A2 and the new value in B2, then in C2 enter:
=(B2 − A2) / ABS(A2) Format that cell as a percentage (Excel and Google Sheets both have a % toolbar button) and the result shows as 25% rather than 0.25 - the formatting handles the × 100 step for you. Wrapping the denominator in ABS() keeps the answer correct if the original value is ever negative. To copy the calculation down a column, drag the fill handle on C2; the relative references update for each row automatically. If a row has an original value of 0, the cell will show a #DIV/0! error, which is the spreadsheet correctly telling you that percentage change from zero is undefined - the same edge case this tool flags.
Percentage increase vs. related calculations
"Percentage increase" is one specific question among a family of percentage problems, and picking the wrong tool is the most common reason people get a confusing answer. Here is how this calculator differs from its closest siblings:
- Percentage change in general: when you want the same math but expect the result might be a decrease as often as an increase, the Percentage Change Calculator is the neutral, signed version of this page - it labels the direction without assuming growth.
- A percentage of a number: if you just need "what is 25% of 120?" rather than a comparison between two numbers, use the Percentage Calculator, which multiplies a value by a percentage instead of dividing a difference.
- A markup on cost: retailers turning a wholesale cost into a selling price are computing a markup - mathematically a percentage increase, but framed around cost and price. The Markup Calculator handles that wording and also shows the resulting margin.
- A discount off a price: a sale that takes a percentage off is a percentage decrease applied to a starting price. The Discount Calculator works out the sale price and the dollars saved directly.
- Experimental error: comparing a measured result against a known true value is a close cousin of percent change; for that, the Percent Error Calculator uses the true value as the base.
All of these share the underlying idea of comparing one number to another, but the base (what you divide by) and the wording differ. When in doubt, ask yourself what the change is being measured against: that quantity is your denominator, and it tells you which calculator fits.
Sources
The percentage-change method on this page follows standard definitions published by U.S. government statistical and educational agencies:
โ ๏ธ Common mistakes & edge cases
Dividing by the new value
Percentage change is always relative to the original value, not the new one. From 120 to 150, divide the 30 difference by 120 (= 25%), not by 150 (which would give a wrong 20%).
Confusing percent change with percentage points
A rate moving from 4% to 5% is a 1 percentage-point change but a 25% increase. Report which one you mean - they describe very different magnitudes.
Starting from zero
If the original value is 0, percentage increase is undefined - you cannot divide by zero. There is no base to grow from, so report the change as an absolute number instead.
Assuming a decrease undoes an increase
A 50% increase then a 50% decrease does not return the original value (100 → 150 → 75). Each step uses a different base, so reversing a gain needs a smaller percentage drop.
❓ Frequently asked questions
How do you calculate percentage increase?
Subtract the original value from the new value, divide the result by the absolute value of the original, and multiply by 100. As a formula: percent change = ((new - old) / |old|) x 100. For example, going from 120 to 150 is (150 - 120) / 120 x 100 = 25% increase.
What is the percentage increase from 120 to 150?
The difference is 150 - 120 = 30. Divide by the original (30 / 120 = 0.25) and multiply by 100 to get a 25% increase. The absolute increase is 30.
What is the difference between percentage increase and percentage change?
They use the same formula. 'Percentage change' is the general term for any difference between two values - it can be positive or negative. 'Percentage increase' specifically describes a positive change, and 'percentage decrease' describes a negative one. A -25% change is the same as a 25% decrease.
Why does the calculator divide by the original value, not the new value?
Percentage change always measures growth relative to the starting point, so the original (old) value is the base. Dividing by the new value instead would answer a different question and is a common mistake. That is also why a 25% increase followed by a 25% decrease does not return you to the start - each step uses a different base.
Can the original value be zero?
No. If the original value is 0, percentage change is undefined because you cannot divide by zero - there is no base amount to compare against. Any growth from 0 is sometimes described as an 'infinite' or 'undefined' percent increase, so report it as an absolute change instead.
How do I calculate a percentage decrease?
Use the same formula. If the new value is smaller than the original, the result is negative, which means a decrease. For example, from 200 to 150: (150 - 200) / 200 x 100 = -25%, i.e. a 25% decrease. This calculator labels negative results as a decrease automatically.
What does it mean if the percentage increase is over 100%?
A result above 100% means the value more than doubled. For example, going from 50 to 150 is a 200% increase, because the new value is three times the original. Any increase greater than 100% indicates the quantity grew by more than its entire original amount.
How do I work backwards from a percentage increase to the new value?
Multiply the original value by (1 + the increase as a decimal). To add 25% to 120, calculate 120 x 1.25 = 150. For a decrease, subtract: 120 reduced by 25% is 120 x 0.75 = 90. This is the reverse of what the calculator does, and it is handy when you know the original number and the percentage but need the final figure.
What is the difference between percentage increase and a percentage of a number?
They answer different questions. 'Percentage increase' compares two numbers and tells you how much one grew relative to the other (120 to 150 is a 25% increase). 'A percentage of a number' just takes a fraction of a single value (25% of 120 is 30). The increase formula divides a difference by the original; finding a percentage of a number multiplies the number by the percentage.
How do I average several percentage increases?
You generally cannot just add them up and divide, because each percentage applies to a different base. If a value grows 10% one year and 20% the next, the two-year growth is 1.10 x 1.20 = 1.32, a 32% total increase, not 30%. To find the average annual growth, take the geometric mean: the square root of 1.32 is about 1.149, so roughly 14.9% per year, not the simple average of 15%.
Does the order of the two values matter?
Yes. The calculator treats the first number as the original (the base) and the second as the new value. Swapping them changes the answer because the denominator changes. From 80 to 100 is a 25% increase, but from 100 to 80 is a 20% decrease. Always enter the earlier or starting value as the original.
How do I express a percentage increase as a fraction or ratio?
Convert the percentage to a fraction over 100 and simplify. A 25% increase is 25/100 = 1/4, meaning the new value is the original plus a quarter of itself, or 5/4 of the original. A 50% increase is 1/2 added on, giving 3/2. Writing it as a ratio of new to old can make mental math faster: 5:4 for a 25% rise.
Why is my percentage increase a very large number?
Large percentages usually mean the original value was small relative to the change. Going from 2 to 50 is a 2,400% increase because 48 is 24 times the starting value of 2. Big percentages are mathematically correct but can be misleading on tiny bases, so it often helps to also report the absolute change alongside the percentage.
💡 Good to know
Quick mental shortcut for round numbers
To add 10% to a number, just shift the decimal one place and add it on: 10% of 250 is 25, so a 10% increase makes 275. For 20%, double that; for 5%, halve it. Stacking these (10% + 5%) lets you estimate a 15% increase without a calculator.
Watch the base when a percentage is reversed
Reversing a percentage increase never uses the same percentage. After a 25% rise, you need only a 20% drop to get back; after a 50% rise, a 33.3% drop. The bigger the increase, the smaller the matching decrease needed to undo it - because the decrease works on a larger number.
Report the absolute number too
A percentage alone can mislead on small bases - a "100% increase" might be a change from 1 to 2. Pairing the percentage with the absolute difference (and the original value) gives readers the context to judge whether the change is meaningful.