How do I calculate X% of Y?

Multiply Y by X and divide by 100. For example, 15% of 200 = (200 × 15) / 100 = 30. Use the 'X% of Y' mode in this calculator.

How do I find what percentage X is of Y?

Divide X by Y and multiply by 100. For example, 30 is what % of 200? = (30 / 200) × 100 = 15%. Use the 'X is what % of Y' mode.

How do I calculate percentage change?

Percentage change = (New value − Original value) / |Original value| × 100. A positive result is an increase, negative is a decrease. Example: from 100 to 125 = (125 − 100) / 100 × 100 = +25%.

How do I increase a number by a percentage?

Result = Original × (1 + Rate/100). Example: increase ₹500 by 18% = 500 × 1.18 = ₹590. Use the 'Increase by %' mode.

Percentage Calculator

⚠️ Not financial advice. Results are illustrative only and should not be used as the basis for any investment, tax, or financial decision. Consult a qualified financial adviser or chartered accountant before acting on any figure shown.

Five types of percentage calculations

X% of Y: find a fraction of a number — e.g. 18% GST on ₹1,000 = ₹180.
X is what % of Y: find a ratio — e.g. you scored 45 out of 60: what % = 75%.
% change: track growth or decline — e.g. revenue went from ₹80L to ₹1Cr: +25%.
Increase by %: apply a markup — e.g. add 20% margin to ₹500 cost price = ₹600.
Decrease by %: apply a discount — e.g. 30% off ₹2,000 = ₹1,400.

Common use cases

Percentage calculators are used everywhere: calculating GST and discounts in retail, tracking investment returns, computing exam scores, finding salary hikes, evaluating business growth, and splitting tips. Knowing how to quickly move between these five modes covers the vast majority of real-world percentage questions.

Real-world examples across contexts

A student scoring 432 out of 500 in their board exam uses the "X is what % of Y" mode to calculate 86.4% before filling their college application form. A small business owner marking up a product that costs ₹850 by 35% uses the "increase by %" mode to arrive at ₹1,147.50 as the selling price. An investor whose mutual fund NAV moved from ₹42.50 to ₹48.75 uses the "% change" mode to see their 14.7% gain and compare it with the benchmark. A salaried employee calculating 18% GST on a ₹12,400 service invoice uses "X% of Y" to get ₹2,232 and verify the total before approving payment.

GST and tax calculations using percentages

India's GST slabs are 5%, 12%, 18%, and 28%. To find the GST amount on a pre-tax price, use the "X% of Y" mode. To find the pre-tax price when you only know the inclusive price, use the reverse formula: pre-tax = inclusive ÷ (1 + rate/100). For example, an inclusive price of ₹1,180 at 18% GST gives a base price of ₹1,180 ÷ 1.18 = ₹1,000. This reverse calculation is used by GST-registered businesses separating input tax from sale prices, and by consumers verifying that a quoted inclusive price matches the stated rate.

Percentage change vs absolute change — why it matters

A salary increase from ₹40,000 to ₹44,000 is an absolute increase of ₹4,000 and a percentage increase of 10%. Both numbers are useful: the absolute tells you the rupee impact on monthly cash flow; the percentage lets you compare the hike against inflation (~5–6% in India) and peer benchmarks. A 7% hike that sounds impressive is actually a real pay cut if inflation is running at 8%. When evaluating investment returns, stock price changes, revenue growth, or salary negotiations, always check both the absolute amount and the percentage change in context.