📊 Math & Algebra

Percentage Calculator

Solve any percentage problem instantly. Find what percent of a number is, percentage change, what percentage X is of Y, and more — all in one free percentage calculator.

📊 What is X% of Y?

What is% of?

📊 X is what % of Y?

is what % of?

📊 Percentage Change

Fromto

📊 Add / Remove a Percentage

+/−%

What Is a Percentage Calculator?

This percentage calculator solves every type of percentage problem you encounter in daily life, school, or work. In short, it is the only percentage calculator you need. Whether you want to find what percentage one number is of another, calculate a percentage increase or decrease, or add and remove percentages from values — this percentage calculator handles all of it in one place.

Percentages appear everywhere. Furthermore, mental percentage calculations are easy to get wrong. Therefore, this percentage calculator gives you instant, accurate answers every time.

How Does This Percentage Calculator Work?

This percentage calculator uses four different calculation modes. Each one solves a different type of percentage problem.

Mode 1 — What is X% of Y?

Result = Y × (X ÷ 100)

Use this mode to find discounts, tips, tax amounts, and commission values. For example, 20% of $150 = $150 × 0.20 = $30.

Mode 2 — X is what % of Y?

Percentage = (X ÷ Y) × 100

Use this mode for exam scores, market share, and proportions. For example, 45 out of 60 = (45 ÷ 60) × 100 = 75%.

Mode 3 — Percentage Change

Change = ((New − Old) ÷ |Old|) × 100

Use this mode to calculate price increases, revenue growth, or weight loss percentages. A negative result means a decrease. A positive result means an increase.

Mode 4 — Add or Remove a Percentage

Add: Result = Value × (1 + Percentage ÷ 100)
Remove: Result = Value × (1 − Percentage ÷ 100)

Use this mode to add GST or VAT to a price, or to remove tax from a total. For example, adding 10% GST to $100 gives $110.

How to Use This Percentage Calculator

Choose the correct mode — identify which type of percentage problem you are solving.
Enter your numbers — fill in the relevant fields for that mode.
Click Calculate — the answer appears instantly below the input.

💡 Not sure which mode to use? Read the question out loud. If it says “what is X% of Y” — use Mode 1. If it says “X is what percent of Y” — use Mode 2. If it asks how much something increased or decreased — use Mode 3.

What Can You Use This Percentage Calculator For?

This percentage calculator is useful in dozens of everyday situations. Here are the most common ones.

Shopping discounts: Use Mode 1 to find 25% off $80 = $20 saving.
Exam scores: Use Mode 2 to find that 38 out of 50 = 76%.
Salary increases: Use Mode 3 to find that going from $60,000 to $66,000 is a 10% increase.
GST and VAT: Use Mode 4 to add 10% GST to $250 = $275 total.
Investment returns: Use Mode 3 to find that a portfolio rising from $10,000 to $11,500 is a 15% gain.
Nutrition and fitness: Use Mode 2 to find what percentage of daily calories come from protein.

Is This Percentage Calculator Accurate?

Yes — this percentage calculator uses standard mathematical formulas and is accurate to multiple decimal places. Results are rounded to four decimal places where needed, then trailing zeros are removed for clarity.

According to Khan Academy’s percentage guide, understanding how to calculate percentages is one of the most practical mathematics skills for everyday life. This percentage calculator makes it accessible to everyone — no maths background required.

Common Percentage Calculator Mistakes

Confusing percentage of vs percentage change: “30 is 10% of 300” is different from “300 increased by 10% to 330.” Use the correct percentage calculator mode for each situation.
Adding percentages directly: A 20% increase followed by a 20% decrease does not return to the original value. The percentage calculator will show the correct result — which is slightly below the starting point.
Using the wrong base for percentage change: Percentage change is always calculated from the original (old) value — not the new value. This percentage calculator uses the correct formula automatically.

Percentage Calculator — Frequently Asked Questions

How do I calculate what percentage one number is of another?

Use Mode 2 of this percentage calculator. Enter the first number (the part) and the second number (the whole). Click Calculate. The percentage calculator divides the part by the whole and multiplies by 100. For example, 30 out of 120 = 25%.

How do I calculate percentage increase using this percentage calculator?

Use Mode 3. Enter the original value in the first field and the new value in the second. The percentage calculator automatically determines whether the change is an increase or decrease and shows the percentage accordingly.

Can I use this percentage calculator for tax calculations?

Yes — use Mode 4 to add tax to a price. Enter the pre-tax price, enter the tax rate percentage, and click Add %. The percentage calculator shows the total including tax. To find the pre-tax price from a tax-inclusive total, enter the total, enter the tax rate, and click Remove %.

What is the difference between percentage and percentage points?

Percentage is a proportion of a whole. Percentage points measure the arithmetic difference between two percentages. For example, rising from 10% to 15% is an increase of 5 percentage points — but it is a 50% increase in percentage terms. This percentage calculator calculates percentage change, not percentage point change.

Is this percentage calculator free?

Yes — this percentage calculator is completely free. There is no registration, no account, and no limit on calculations. It runs entirely in your browser so your data is never sent to any server.