How to Calculate Percentage Increase – Step-by-Step with Examples

Percentage increase is one of the most commonly needed calculations in daily life — whether you're analysing salary hikes, stock market gains, product price changes, or exam score improvements. This guide explains the formula, walkthrough examples, and common mistakes to avoid.

What is Percentage Increase?

Percentage increase measures how much a value has grown relative to its original value, expressed as a percentage. It tells you not just by how much something increased, but how significant that increase was proportionally. A ₹5,000 increase on a ₹10,000 salary is a 50% increase — far more significant than the same ₹5,000 on a ₹1,00,000 salary (5%).

The Percentage Increase Formula

This formula has three components: the original value (the starting point), the new value (the end point), and the change (subtraction of the two). Dividing by the original value normalises the change and multiplying by 100 converts the decimal to a percentage.

Step-by-Step Example

Let's calculate the percentage increase in a software developer's salary from ₹60,000/month to ₹78,000/month.

1. Step 1: Find the change: ₹78,000 − ₹60,000 = ₹18,000
2. Step 2: Divide by the original value: ₹18,000 / ₹60,000 = 0.30
3. Step 3: Multiply by 100: 0.30 × 100 = 30%

Interpretation: The developer received a 30% salary hike.

More Real-World Examples

• Stock Market: Nifty 50 went from 18,000 to 22,500. Increase = (22,500−18,000)/18,000 × 100 = 25%
• Petrol Price: Petrol rose from ₹95 to ₹106/litre. Increase = (106−95)/95 × 100 = 11.58%
• Exam Score: You scored 65% last term and 78% this term. Increase = (78−65)/65 × 100 = 20%
• Product Price: A phone went from ₹25,000 to ₹29,990. Increase = (29,990−25,000)/25,000 × 100 = 19.96%

How to Find the New Value from a Known Percentage Increase

If you know the original value and the percentage increase, find the new value with:

Example: Price increases by 12% from ₹5,000 → New Price = ₹5,000 × 1.12 = ₹5,600

Common Mistakes to Avoid

• Using the wrong base: Always divide by the original (old) value, not the new value.
• Confusing percentage increase with percentage points: If interest rate goes from 5% to 7%, it increased by 2 percentage points but a 40% increase in relative terms.
• Forgetting to multiply by 100: Without this step, the result is a decimal, not a percentage.
• Applying sequential percentages incorrectly: A 20% increase followed by a 20% decrease does NOT return to the original. The net change is −4%.

Frequently Asked Questions