How do I calculate X% of Y?

Multiply Y by X and divide by 100. E.g., 25% of 200 = (25 × 200) / 100 = 50.

How do I find what percentage X is of Y?

Divide X by Y and multiply by 100. E.g., 50 is what % of 200? = (50 / 200) × 100 = 25%.

How do I calculate percentage change?

% Change = ((New − Old) / |Old|) × 100. A positive result is an increase, negative is a decrease. E.g., from 100 to 125 = +25%.

How do I add a percentage to a number?

New value = Original × (1 + Rate/100). E.g., 200 + 10% = 200 × 1.10 = 220.

How do I calculate percentage increase or decrease?

Percentage change = (New Value - Old Value) / Old Value x 100. If a stock goes from Rs. 200 to Rs. 250, the increase is (250-200)/200 x 100 = 25%. If it drops from Rs. 250 to Rs. 200, the decrease is (200-250)/250 x 100 = -20%. Note that a 25% gain followed by a 25% loss does not return to the original value - you end up at 93.75 (asymmetry of percentages). Always compute from the original base.

Percentage Calculator

Calculate percentages instantly - find X% of Y, percentage change, add or subtract percentages.

Value A

Value B

Results

What is 25% of 200?50

25 is what % of 200?12.5%

% change from 25 to 200+700%

200 + 25%250

200 − 25%150

Enter any two values - all five percentage relationships are calculated instantly.

About the Percentage Calculator

Percentage calculations appear in almost every aspect of daily life - from GST and discounts to exam scores, interest rates, salary hikes, and investment returns. Despite being a core mathematical concept, many people make errors when dealing with percentages, especially with percentage change (which is not the same as percentage points). This calculator handles all common percentage problems instantly.

Core Percentage Formulas

% of X: (P/100) × X · X is what % of Y: (X/Y) × 100 · % change: ((New − Old)/Old) × 100

Percentage point change ≠ percentage change · E.g., 10% → 15% is a 5 percentage point increase, but a 50% relative increase

Worked Example

Salary hike from ₹8 lakh to ₹9.2 lakh per annum

Old Salary:₹8,00,000

New Salary:₹9,20,000

Percentage increase = ((9.2 − 8) / 8) × 100 = 15% hike

Tips & Insights

1
A 20% discount followed by a 20% price increase does NOT bring you back to the original price (net: −4%).
2
When comparing interest rates vs inflation, use real return = ((1 + nominal) / (1 + inflation)) − 1.
3
GST is calculated on base price, not on the final price - use the 'extract GST' mode when working backwards.
4
Percentage change and absolute change tell different stories - a 10% raise on ₹5L is very different from 10% on ₹50L.
5
CAGR (Compound Annual Growth Rate) is a percentage that measures true annual growth rate for investments over time.

Why this matters for you

Misunderstanding percentages is one of the most common financial mistakes - whether it's misreading a salary hike letter, overpaying on a 'flat 30% off' sale, or comparing EMIs without considering effective annual rate. Our calculator covers every variation so you can verify any percentage claim in seconds.