Calculate percentage increase or decrease between an original and a new value. Free online percentage change calculator for prices, salary, sales and marks.

What is the Percentage Change Calculator?

The Percentage Change Calculator tells you how much a value has grown or shrunk relative to where it started. Enter the original value and the new value, and it returns the change as a percentage, positive for an increase and negative for a decrease. It is the quickest way to describe a salary hike, a price rise, a fall in monthly sales or an improvement in exam marks.

Business owners tracking revenue, investors checking a stock move, and students solving textbook problems all use the same formula: the difference divided by the original value, times 100. Toolnest divides by the absolute original value, so the sign of the answer always matches the direction of the move, even when you start from a negative number such as a loss. The calculation happens in your browser.

How to use the Percentage Change Calculator

Type the starting figure in Original value (nonzero), for example last year's salary of 45000.
Type the latest figure in New value, for example 52000.
Press Calculate. A positive result means an increase; a negative result means a decrease.
Read the note under the result, which reminds you the change is divided by the absolute original value.
Copy the result if you need it elsewhere, or press Reset to compare another pair of numbers.

Features

Shows growth or decline as a signed percentage
Uses the absolute original value, so negative starting points give sensible signs
Rejects a zero original value with a clear message
Accepts decimals and negative numbers
Copy button and Reset button for quick repeat checks

Why use this percentage change calculator

Compare changes of different sizes on the same scale
Avoid the common mistake of dividing by the new value
Get a ready-to-quote figure for reports and presentations
Works offline-style in the browser with nothing uploaded

Formula used

Change (%) = (new − original) ÷ |original| × 100.

Examples

Salary hike

Input: Original value 45000, New value 52000

Result: 15.5556% Change divided by the absolute original value. A raise from ₹45,000 to ₹52,000 is roughly a 15.56% increase.

Drop in monthly sales

Input: Original value 1200, New value 950

Result: -20.8333% Change divided by the absolute original value. Sales falling from 1,200 to 950 units is about a 20.83% decrease.

Loss that has narrowed

Input: Original value -100, New value -80

Result: 20% Change divided by the absolute original value. A loss shrinking from -100 to -80 is shown as a 20% improvement because the tool divides by the absolute original value.

Results are estimates for general information, not financial, medical, legal, tax, or property advice. Confirm important figures with the relevant institution or a qualified professional.

Percentage Change Calculator: frequently asked questions

What is the formula for percentage change?

Percentage change = (new value − original value) ÷ original value × 100. Toolnest uses the absolute value of the original in the denominator, so the formula becomes (new − original) ÷ |original| × 100. For positive starting values the two are identical; for example, 80 to 100 gives (100 − 80) ÷ 80 × 100 = 25%.

How do I calculate percentage decrease?

Use the same calculator. Put the higher starting figure in Original value and the lower figure in New value, and the result comes out negative. Moving from 1200 to 950 returns -20.8333%, which means a decrease of about 20.83%. You do not need a separate decrease tool or a different formula.

Why can't the original value be zero?

Percentage change measures the move relative to the starting point, so the original value is the divisor. Dividing by zero has no meaning, which is why the calculator shows the message 'Original value cannot be zero.' If something grew from nothing, describe it as an absolute change, for example 'up by 500 units', rather than as a percentage.

Is percentage change the same as percentage point change?

No. If an interest rate moves from 8% to 10%, that is a change of 2 percentage points but a 25% percentage change, because 2 is a quarter of 8. Enter 8 and 10 here and you get 25%. Use percentage points when comparing two rates directly, and percentage change when describing relative growth.

How many decimal places does the answer show?

The result is shown with up to 4 decimal places, so a raise from 45000 to 52000 appears as 15.5556%. Whole-number changes such as 25% are shown without trailing zeros, and large figures use Indian digit grouping. Round further to suit your report, for example 15.56% or 15.6%.