Percentage Increase & Decrease Calculator

Imagine this: Sarah walks into a store and sees her favorite jacket. Yesterday it was $80, but today the tag shows $60. She wonders, “How big of a discount is this really?”

At the same time, John, her friend, just got a raise. His salary went from $2,500 to $2,750 a month. He’s excited, but he also wants to know: “What’s the percentage increase in my pay?”

Different situations, same question: How much did things change in percentage terms?

This is where the Percentage Increase & Decrease Calculator steps in.

What is this calculator, in simple words?

It’s a tool that compares two numbers — the original value and the new value — and tells you whether the change is an increase or a decrease, and by how many percent.

It answers questions like:

• “How much cheaper is this sale item?”
  
• “What’s my raise in percentage terms?”
  
• “How much weight did I lose compared to where I started?”
  
• “How much did my investment grow?”
  

In short: It translates plain numbers into meaningful insights.

The Formula (don’t worry, it’s simple)

Here’s the magic behind the scenes:

Percentage Change = ((New Value – Original Value) ÷ Original Value) × 100

• If the result is positive → it’s a percentage increase.
  
• If the result is negative → it’s a percentage decrease.
  

How the Calculator Works – Step by Step (like a story unfolding)

Let’s go back to Sarah’s jacket:

1. Enter the original price: 80
   
2. Enter the new price: 60
   
3. Calculator does the math:
   
   • Difference = 60 − 80 = −20
     
   • Divide by original = −20 ÷ 80 = −0.25
     
   • Multiply by 100 = −25%
     
4. The result appears: 25% Decrease.
   

Sarah smiles. She just got a quarter off the price.

Now John tries his salary raise:

1. Original salary: 2,500
   
2. New salary: 2,750
   
3. Math behind it:
   
   • Difference = 2750 − 2500 = 250
     
   • Divide by original = 250 ÷ 2500 = 0.10
     
   • Multiply by 100 = 10%
     
4. The result: 10% Increase.
   

John now proudly tells his friends, “I got a 10% raise!”

Real-Life Extras You’ll Love

• Consecutive changes aren’t additive. If something rises 20% and then falls 20%, it doesn’t come back to where it started. It ends up lower. (100 → 120 → 96, which is actually a 4% decrease overall).
  
• 100% increase means double. A $50 item with a 100% increase costs $100.
  

Percentage points are different. If interest goes from 3% to 5%, that’s 2 percentage points higher, but a 66.7% increase.