How do I calculate percentage?

To find X% of Y: multiply Y by X and divide by 100. Example: 15% of 80 = (80 × 15) ÷ 100 = 12.

How do I calculate percentage increase?

Percentage increase = ((New Value − Old Value) ÷ Old Value) × 100. Example: from 50 to 75 = ((75−50)÷50)×100 = 50% increase.

How to find what percentage one number is of another?

Divide the part by the whole, then multiply by 100. Example: what percent is 30 of 120? (30÷120)×100 = 25%.

Percentage Calculator - Calculate %, Increase, Decrease

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Percentage Calculator

Calculate any type of percentage — results update as you type

🔢 What is X% of Y?

What is % of ?

Answer: —

❓ What % is X of Y?

is what % of ?

Answer: —

📈 Percentage Increase / Decrease

From to

Change: —

➕ Add or Subtract a Percentage

Result: —

🔄 Reverse Percentage (Find Original)

After a % increase, result is

Original value was: —

How to Calculate Percentages

A percentage is a way of expressing a number as a fraction of 100. The word "percent" means "per hundred." Percentages are used everywhere — from discounts and taxes to exam scores, interest rates, and statistics.

This calculator handles all five common types of percentage calculations. Just type your numbers and results appear instantly — no button press needed.

Percentage Formulas

X% of Y = Y × X ÷ 100
What % is A of B = (A ÷ B) × 100
% Change = ((New − Old) ÷ Old) × 100
Add X% to Y = Y × (1 + X/100)
Subtract X% = Y × (1 − X/100)
Original value = Result ÷ (1 + X/100)

📘 Example Scenarios

Scenario 1 — Priya calculates GST on a purchase 🧾

Priya buys a laptop worth ₹50,000 and wants to know the price after 18% GST. She uses "Add 18% to 50,000" and gets ₹59,000. The GST amount is ₹9,000. This helps her budget accurately.

Scenario 2 — Mark checks his test score 📝

Mark scored 68 out of 85 in a test and wants to know his percentage. He uses "What % is 68 of 85?" and gets 80%. He also checks how much his score improved — from 55 last time to 68 this time, that's a 23.6% increase.

Frequently asked questions

Multiply the number by 0.20 (or divide by 5). Example: 20% of 350 = 350 × 0.20 = 70. Mental shortcut: find 10% (divide by 10) then double it.

Subtract old value from new, divide by old value, multiply by 100. Example: price went from ₹400 to ₹500 → ((500−400)÷400)×100 = 25% increase.

Use the reverse percentage: if you paid ₹800 after a 20% discount, original = 800 ÷ (1−0.20) = 800 ÷ 0.80 = ₹1,000.

Percentage points are the arithmetic difference between two percentages. If interest rate goes from 5% to 7%, that's a 2 percentage point increase — but a 40% increase in the rate itself. The distinction matters in finance and economics.