Percentage Increase & Decrease Calculator

Share

A percentage increase and decrease calculator helps you find how much a value has increased or decreased compared with its original value. You can also use it to calculate a new value after applying a percentage increase or decrease.

For example, you can calculate:

  • the percentage increase from 200 to 260
  • the percentage decrease from 500 to 400
  • a 15% increase on ₹2,000
  • a 20% decrease on ₹5,000

Find Percentage Increase or Decrease

Increase or Decrease a Value by a Percentage

Enter your values above to calculate the result instantly, along with the calculation steps.

What Can You Calculate With This Tool?

This calculator handles two common percentage problems.

1. Find the Percentage Increase or Decrease

Use this when you know the original value and the new value, but want to find the percentage change between them.

Example:

A price increases from ₹200 to ₹260.

  • Difference = ₹260 − ₹200 = ₹60
  • Percentage increase = 30%

This answers questions such as:

  • What is the percentage increase?
  • How much did the value increase in percentage?
  • What is the percentage decrease?
  • What percentage did the value drop?
  • What is the percentage gain?

2. Increase or Decrease a Value by a Percentage

Use this when you know the original value and a percentage, and want to calculate the resulting value.

Example:

Increase ₹2,000 by 15%.

  • 15% of ₹2,000 = ₹300
  • New value = ₹2,000 + ₹300 = ₹2,300

You can also calculate reductions in the same way.

Example:

Decrease ₹2,000 by 15%.

  • 15% of ₹2,000 = ₹300
  • New value = ₹2,000 − ₹300 = ₹1,700

How to Calculate Percentage Increase

Percentage increase tells you how much a value has grown compared with its original value.

Percentage Increase Formula

Percentage Increase = ((New Value − Original Value) ÷ Original Value) × 100

Example

Suppose a product price increases from ₹500 to ₹650.

Step 1: Find the increase

₹650 − ₹500 = ₹150

Step 2: Divide the increase by the original value

₹150 ÷ ₹500 = 0.30

Step 3: Convert it to a percentage

0.30 × 100 = 30%

So, the price increased by 30%.

How to Calculate Percentage Decrease

Percentage decrease tells you how much a value has fallen compared with its original value.

Percentage Decrease Formula

Percentage Decrease = ((Original Value − New Value) ÷ Original Value) × 100

Example

Suppose a price falls from ₹800 to ₹600.

Step 1: Find the decrease

₹800 − ₹600 = ₹200

Step 2: Divide the decrease by the original value

₹200 ÷ ₹800 = 0.25

Step 3: Convert it to a percentage

0.25 × 100 = 25%

So, the value decreased by 25%.

How to Increase a Number by a Percentage

When you want to increase a value by a known percentage, first calculate the percentage amount and then add it to the original value.

Formula

Percentage Amount = Original Value × (Percentage ÷ 100)

New Value = Original Value + Percentage Amount

Example

Increase 500 by 20%.

20% of 500:

500 × 20 ÷ 100 = 100

Add the increase to the original value:

500 + 100 = 600

So, 500 increased by 20% is 600.

You can use the calculator above for price increases, salary increases, quantity increases, growth calculations, and other similar problems.

How to Decrease a Number by a Percentage

To decrease a value by a known percentage, calculate the percentage amount and subtract it from the original value.

Formula

Percentage Amount = Original Value × (Percentage ÷ 100)

New Value = Original Value − Percentage Amount

Example

Decrease 500 by 20%.

20% of 500:

500 × 20 ÷ 100 = 100

Subtract the decrease:

500 − 100 = 400

So, 500 decreased by 20% is 400.

Percentage Increase and Decrease Formula

Here are the main formulas in one place:

CalculationFormula
Percentage increase(New − Original) ÷ Original × 100
Percentage decrease(Original − New) ÷ Original × 100
Increase a value by X%Original × (1 + X ÷ 100)
Decrease a value by X%Original × (1 − X ÷ 100)

The original value is the reference point when calculating a percentage increase or decrease.

Percentage Increase vs Percentage Change

Percentage increase and percentage change are closely related, but the wording can be different depending on what you are trying to describe.

For example, if a value changes from 500 to 600:

Percentage increase:

(600 − 500) ÷ 500 × 100 = 20%

Because the new value is higher, the result is a 20% increase.

Percentage change can be expressed using the same calculation when comparing an original value with a new value. However, when discussing a general change, the result can be positive or negative to indicate the direction.

For a dedicated calculation of percentage change, see our Percentage Change Calculator.

Percentage Points vs Percentage Increase

Percentage points and percentage increase are not the same thing.

For example, suppose a rate increases from 4% to 5%.

The difference is:

5% − 4% = 1 percentage point

But the relative increase is:

(5 − 4) ÷ 4 × 100 = 25%

So the rate increased by 1 percentage point, which is a 25% relative increase.

This distinction is particularly useful when comparing percentages themselves.

Can a Percentage Increase and Decrease Cancel Each Other Out?

Not necessarily.

A percentage increase and the same percentage decrease do not usually return a value to its starting point.

For example, start with ₹1,000.

Increase by 20%

₹1,000 + 20% = ₹1,200

Now decrease ₹1,200 by 20%:

20% of ₹1,200 = ₹240

₹1,200 − ₹240 = ₹960

The final value is ₹960, not ₹1,000.

This happens because the second 20% is calculated using a different base value.

Percentage Increase and Decrease Examples

Original ValueNew ValueResult
10012020% increase
20026030% increase
50040020% decrease
80060025% decrease
1,0001,25025% increase
2,0001,50025% decrease

These examples use the original value as the base for calculating the percentage increase or decrease.

Where Are Percentage Increases and Decreases Used?

Percentage increases and decreases are common in everyday calculations, including:

  • Price changes: finding how much a product price increased or decreased
  • Salary increases: calculating the amount and new salary after a percentage hike
  • Business: measuring growth or reduction in sales and revenue
  • Investments: calculating percentage gains or losses
  • Discounts: finding the value after a percentage reduction
  • Quantities: calculating increases or reductions in measurements
  • Performance: measuring percentage improvement or decline

The same formulas can be used regardless of whether the values represent money, quantities, scores, or other numerical measurements.

Frequently Asked Questions

How do you calculate percentage increase?

Subtract the original value from the new value, divide the difference by the original value, and multiply by 100.
Percentage Increase = ((New Value − Original Value) ÷ Original Value) × 100

How do you calculate percentage decrease?

Subtract the new value from the original value, divide the difference by the original value, and multiply by 100.
Percentage Decrease = ((Original Value − New Value) ÷ Original Value) × 100

What is the formula for percentage gain?

Percentage gain is calculated by dividing the gain by the original value and multiplying by 100.
Percentage Gain = (Gain ÷ Original Value) × 100
For example, if an investment increases from ₹1,000 to ₹1,200, the gain is ₹200 and the percentage gain is 20%.

How do you calculate a percentage increase in price?

Subtract the original price from the new price, divide the difference by the original price, and multiply by 100.
For example, a price increasing from ₹500 to ₹600 represents a 20% increase.

How do you calculate percentage reduction?

Percentage reduction is another way of describing a percentage decrease.
Percentage Reduction = ((Original Value − New Value) ÷ Original Value) × 100
For example, reducing a value from 1,000 to 800 represents a 20% reduction.

How do you calculate a new value after a percentage increase?

Multiply the original value by 1 + percentage ÷ 100.
For example:
₹1,000 × (1 + 20 ÷ 100) = ₹1,200

How do you calculate a new value after a percentage decrease?

Multiply the original value by 1 − percentage ÷ 100.
For example:
₹1,000 × (1 − 20 ÷ 100) = ₹800

Can the percentage decrease be greater than 100%?

For a standard decrease from a positive original value to a non-negative value, the decrease cannot exceed 100%. A 100% decrease means the value has fallen to zero.