Percentage Calculator
that just works.

Whether you're a student checking your exam score, a shopper hunting for the best deal, or a professional working with data, this percentage calculator is built for you. It covers five common percentage problems — all in one place — with no account required and nothing to install. Enter your numbers and get an accurate answer instantly.

What Can You Calculate?

This tool covers five types of percentage calculations, each designed for a specific real-world need. Every tool is on the same page, so you can switch between them without starting over:

• Percentage Calculator — Three modules in one:
  • Module 1: What is P% of V? (e.g., What is 20% of 500?)
  • Module 2: X is what % of Y? (e.g., 40 is what % of 200?)
  • Module 3: X is P% of what? (e.g., 30 is 15% of what number?)
• Percentage of Number — Answers: What % is X of Y?
• Percentage Change Calculator — Two modes:
  • Mode A: Find the percentage change from Value A to Value B (increase or decrease)
  • Mode B: Find the new value after a percentage increase or decrease
• Discount Calculator — Calculates the final price after applying a percentage discount
• Tip Calculator — Calculates tip amount and total bill based on a tip percentage

How to Use the Percentage Calculator

Say you want to know what 20 percent of 500 is. Open Module 1 of the Percentage Calculator, type in 20 as the percentage and 500 as the value — the result appears instantly: 100. No formula needed, no app to download, no extra steps.

The Percentage Change Calculator is just as simple. Switch to Mode A, enter your starting value and ending value, and the tool calculates the percentage increase or percentage decrease automatically. For example, if a product dropped from $80 to $60, you'd see a 25% decrease in under a second.

Every tool on this page follows the same approach: fill in what you know, and the calculator finds what you're missing. Most calculations take less than five seconds.

The Percentage Formula — Made Simple

The core percentage formula is: Percentage = (Part ÷ Whole) × 100. This single equation drives all three modules inside the main Percentage Calculator — but each one applies it differently. Module 1 multiplies the whole by a percentage to find the part. Module 2 divides the part by the whole to return the percentage. Module 3 reverses the equation, dividing the part by the percentage to recover the original whole. The math is the same each time — only the unknown changes. You don't need to memorize any of this. Just pick the right module and enter your numbers.

Common Use Cases

• Percentage Calculator: Check exam results, calculate homework grades, or measure how much of a budget has been used.
• Percentage of Number: Compare survey responses, analyze market share, or find what fraction one figure is of a larger total.
• Percentage Change Calculator: Track price changes over time, calculate salary hikes, or monitor weight loss and fitness progress.
• Discount Calculator: Find the final sale price on clothing, electronics, or any item with a percentage markdown before you buy.
• Tip Calculator: Calculate the right tip amount and split a restaurant bill easily, with no mental math required.

Why Use an Online Percentage Calculator?

Doing percentage calculations by hand leaves too much room for error — especially when the numbers aren't round or simple. This tool gives you instant, accurate results with no effort and no formulas to look up. It works on any device, including mobile, so you can calculate percentage wherever you are. Whether you need to find percentage change, apply a discount, or figure out a fair tip, all five tools are here in one place and ready to use.

FAQ

Frequently Asked Questions

Q1What is a percentage calculator?

A percentage calculator is a free online tool that helps you solve any percentage-related math problem instantly — without doing the calculation by hand. It covers common questions like "What is X% of Y?", "X is what percent of Y?", and "X is P% of what number?". Whether you're a student, shopper, or professional, it saves time and eliminates errors.

Q2What is X% of Y — how do I calculate it?

To find X% of Y, multiply Y by X and divide the result by 100. For example, 20% of 500 = (500 × 20) ÷ 100 = 100. You can use Module 1 of this calculator to get the answer instantly — just enter the percentage and the value.

Q3How do I find what percentage one number is of another?

To find what percentage X is of Y, divide X by Y and multiply by 100. For example, 40 is what percent of 200? → (40 ÷ 200) × 100 = 20%. Use the "X is what % of Y?" module above to solve this in one click.

Q4How do I calculate a percentage increase or decrease?

Percentage change = [(New Value − Old Value) ÷ Old Value] × 100. If the result is positive, it's an increase; if negative, it's a decrease. For example, a price going from ₹400 to ₹500 is a 25% increase. Use the Percentage Change Calculator on this page to get the result instantly.

Q5How do I find the new value after a percentage increase or decrease?

Multiply the original value by (1 + percentage/100) for an increase, or (1 − percentage/100) for a decrease. For example, a 10% increase on 200 → 200 × 1.10 = 220. Use Mode B of the Percentage Change Calculator above — enter the original value and the percentage, and it does the rest.

Q6How does the discount calculator work?

The discount calculator finds the final price after applying a percentage off. Enter the original price and the discount percentage, and it instantly shows you the discounted price and how much you save. For example, 30% off ₹1,000 = final price of ₹700, saving you ₹300.

Q7How do I calculate a tip using the tip calculator?

Enter your total bill amount and the tip percentage you want to leave (e.g. 10%, 15%, or 20%). The tip calculator instantly shows the tip amount and the final total you need to pay. For example, a 15% tip on a ₹800 bill = ₹120 tip, making the total ₹920.

Q8What is the basic percentage formula?

The basic percentage formula is: Percentage = (Part ÷ Whole) × 100. This formula is the foundation for all percentage calculations — whether you're finding a discount, calculating exam scores, or comparing two values. All modules on this calculator are built on this formula.

Q9Can I use this calculator for exam marks and grades?

Yes — the percentage calculator is widely used by students to calculate their percentage of marks obtained. Simply enter your total marks scored as the "Part" and the maximum marks as the "Whole". For example, scoring 450 out of 500 → (450 ÷ 500) × 100 = 90%.

Q10Is this percentage calculator free and accurate?

Yes, this tool is completely free with no signup required. All calculations run directly in your browser — no data is sent to any server. The results are mathematically precise, making it reliable for academic, financial, and everyday use.

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