Percentage Increase Calculator

Use our free Percentage Increase Calculator to instantly find the percentage change between two numbers, view the difference and formula, or calculate percentage decreases and increases.

Calculation Mode & Format

Choose which variable you want to solve for or load a quick real-world preset.

Select What to Calculate

Quick Scenario Presets

What-if Growth Simulator

Simulate how adjusting the per-period percentage growth rate or compounding over multiple periods impacts your final value.

Adjust Periodic Rate (Additive %)0%

Compound Over Periods (n)1 Period

Base Final Value

150

(+25% base change)

Simulated Final Value

150

(+25% total over 1p)

Projected Value Variance

Difference from base final value (+0 percentage-point shift in total growth).

How to Calculate Percentage Increase

Calculating the percentage increase between two numbers measures how much a new value has grown relative to its original starting baseline. Follow these steps to calculate percentage increase manually or with the calculator above:

Identify your original value (starting number) and new value (final ending number).

Subtract the original value from the new value to find the absolute difference (Increase = New Value − Original Value).

Divide that difference by the original starting value to get the relative decimal change.

Multiply the decimal by 100 to convert the result into a percentage (%).

Use the calculator modes above to also increase a number by a percentage or find an original pre-increase value.

Why Calculate Percentage Increase?

Expressing growth as a percentage standardizes changes onto a per-100 scale so you can compare small and large numbers on equal footing—the same methodology outlined by the U.S. Bureau of Labor Statistics for Calculating Percentage Changes in economic and consumer data:

Price & Cost Changes: Compare retail markups, rent increases, utility bills, and supplier quotes.
Salary & Revenue Growth: Measure pay raises, sales growth, and year-over-year performance metrics.

Percentage Increase Formula

As explained in OpenStax's Guide to Percent Increase and Decrease, the standard percentage increase formula divides the change between the new value and the original value by the original starting value, then multiplies by 100:

Calculate the Difference

Subtract the original starting value from the new ending value: Difference = New Value − Original Value.

Divide by the Original Value

Divide the difference by the original starting value to find the relative growth ratio (e.g., 20 ÷ 80 = 0.25).

Multiply by 100

Multiply the decimal ratio by 100 to express the result as a percentage (0.25 × 100 = 25%).

Zero & Negative Baselines

For positive baselines, both formulas above give the exact same answer. If the starting value is 0, percentage increase is mathematically undefined (division by zero). If the starting value is negative, dividing by |Original Value| reflects upward direction on the number line, whereas dividing by the signed Original Value preserves algebraic multiplier consistency.

Percentage Increase Examples

See how the percentage increase formula works across three everyday scenarios: product price changes, salary raises, and business growth over time.

Example 1 • Retail & Pricing

Price Increase Example

A monthly software plan rises from $80 to $100. Subtracting $80 from $100 gives a +$20 increase. Dividing $20 by the $80 original price gives 0.25, or a 25% increase—the same baseline method national agencies use to track Inflation and Price Indices.

Original Price$80.00

New Price$100.00

Formula((100 − 80) ÷ 80) × 100

Percentage Increase+25% (1.25×)

Example 2 • Income & HR

Salary Increase Example

An employee's annual salary increases from $65,000 to $72,800. The dollar raise is $7,800. Dividing $7,800 by the $65,000 starting salary yields 0.12, which is a 12% pay raise.

Starting Salary$65,000

New Salary$72,800

Formula(7,800 ÷ 65,000) × 100

Salary % Increase+12% (+$7,800)

Example 3 • Business Metrics

Percentage Increase Over Time

A store's monthly orders grow from 1,250 orders in Q1 to 1,600 orders in Q2. The gain of 350 orders divided by the 1,250 baseline equals 0.28, or 28% growth over the quarter.

Baseline Orders1,250

Current Orders1,600

Formula(350 ÷ 1,250) × 100

Period % Increase+28% (1.28×)

How to Increase a Number by a Percentage

When you know your starting number and want to add a specific percentage markup (such as adding 15% to $200), convert the percentage to a decimal, add 1 to form the growth multiplier, and multiply by the original value:

Formula to Add a Percentage

New Value = Original × (1 + % Increase ÷ 100)

Worked Example: Increase $200 by 15% → $200 × (1 + 15 ÷ 100) = $200 × 1.15 = $230 (an increase of $30).

When a percentage increase repeats across multiple periods, each new gain builds on top of the previous period's ending total using Original × (1 + r)^n—a principle explained in Investor.gov's guide to Understanding Compound Interest, which you can model directly in our Advanced Specs tab and What-if Growth Simulator above.

Percentage Increase Multiplier Reference Table

Quick decimal growth multipliers for common percentage increases applied to 100.

% Increase	Decimal Multiplier	100 Increased by %
+5%	× 1.05	105
+10%	× 1.10	110
+15%	× 1.15	115
+20%	× 1.20	120
+25%	× 1.25	125
+50%	× 1.50	150
+100% (Double)	× 2.00	200
+200% (Triple)	× 3.00	300

How to Find the Original Value Before an Increase

To reverse a percentage increase and recover the original starting number, divide the final number by the growth multiplier (1 + % Increase ÷ 100). Never subtract the percentage directly from the final value, because the original percentage was calculated on a smaller starting base.

Reverse Percentage Formula & Example

Original Value = Final Value ÷ (1 + % Increase ÷ 100)

If a bill totals $108 after an 8% tax increase, the pre-tax price is $108 ÷ 1.08 = $100.00 (whereas subtracting 8% of $108 would wrongly give $99.36).

Percentage Increase vs. Percentage Decrease

When the new value is smaller than the original value, the standard formula produces a negative percentage change, representing a percentage decrease. Because percentages always depend on the starting baseline, equal upward and downward steps do not cancel out to zero.

Worked Decrease & Asymmetry Example

% Decrease = ((Original − New) ÷ Original) × 100

Dropping from $100 to $80 is a 20% decrease (20 ÷ 100), but recovering from $80 back to $100 requires a 25% increase (20 ÷ 80). Similarly, 100 + 20% = 120, and 120 − 20% = 96 (a net 4% decrease).

Percentage Increase vs. Percentage Points

When comparing two values that are already percentages—such as interest rates, tax brackets, or conversion rates—it is critical to distinguish between relative percentage increase and percentage points (pp):

Percentage Increase (%)

Measures relative growth compared to the starting baseline (V₂ − V₁) ÷ V₁. Moving from a 4.0% rate to a 5.0% rate is a +25% relative increase because (5 − 4) ÷ 4 = 0.25.

Percentage Points (pp)

The direct arithmetic difference between two percentages. Moving from 4.0% to 5.0% is an absolute change of +1.0 percentage point (+1.0 pp).

Symmetric Percentage Difference

Divides the absolute difference by the midpoint average of two positive numbers |A − B| ÷ [(A + B)/2]. Used when comparing two peer values with no chronological order.

Frequently Asked Questions

Common questions about calculating percentage increase, decreases, markups, and reverse percentages.

How do you calculate percentage increase between two numbers?

Subtract the original starting number from the new final number to find the amount of increase. Divide that difference by the original starting number, then multiply the result by 100. For example, from 50 to 65: ((65 − 50) ÷ 50) × 100 = 30% increase.

How do I increase a number by a specific percentage?

Convert the percentage to a decimal by dividing by 100, add 1 to get the growth multiplier, and multiply by your starting number. To increase $200 by 15%, calculate $200 × (1 + 0.15) = $200 × 1.15 = $230.

Why doesn't a 20% increase followed by a 20% decrease return to the original number?

Because the second percentage change is calculated against the new, larger baseline. If 100 increases by 20%, it becomes 120. Taking 20% off 120 subtracts 24 (120 × 0.20), leaving 96—a net 4% decrease.

How do I find the original number before a percentage increase?

Divide the final number by (1 + percentage increase ÷ 100). Do not subtract the percentage from the final number. For example, if an item costs $115 after a 15% increase, the original price is $115 ÷ 1.15 = $100.

How are zero and negative starting baselines handled?

If the starting value is 0, percentage increase is undefined because dividing by zero is impossible. For negative starting values, the standard algebraic convention divides by V₁ so forward and reverse multipliers stay consistent, while the absolute-baseline convention divides by |V₁|. You can switch between both in the Advanced Specs tab.

How do you calculate percentage increase in Excel or Google Sheets?

If your original value is in cell A2 and your new value is in cell B2, enter the formula =(B2-A2)/A2 (or =(B2-A2)/ABS(A2) for an absolute baseline) and format the cell as a Percentage (%). To increase cell A2 by 15%, enter =A2*(1+15%).