Percentage Calculator

Solve any percentage problem instantly! Calculate percentages, increases, decreases, discounts, tips, and more with step-by-step solutions.

Select Calculation Type

Basic Percentage Calculator

Calculate what percentage one number is of another.

% of
people

Common Examples

Percentage Calculation

Select a calculation type and enter values to see detailed percentage calculations with step-by-step explanations.

Understanding Percentages: The Foundation of Everyday Math

A percentage is a way of expressing a number as a fraction of 100. The word "percent" comes from the Latin "per centum," meaning "by the hundred." Percentages are used everywhere in daily life - from shopping discounts and restaurant tips to bank interest rates and statistical data.

How to Calculate Percentages: The Core Formula

The Fundamental Percentage Formula:

Percentage = (Part / Whole) × 100

This simple formula is the basis for all percentage calculations. To find what percentage one number is of another, divide the part by the whole and multiply by 100.

Practical Applications of Percentages

Shopping & Discounts

Calculate sale prices, compare discounts, and determine final prices after markdowns. Essential for smart shopping and budgeting.

Example: A $120 item with 25% off = $90 final price

Finance & Banking

Calculate interest rates, loan payments, investment returns, and compare financial products. Crucial for personal finance management.

Example: 5% annual interest on $1,000 = $50 yearly return

Business & Pricing

Determine profit margins, calculate markups, analyze sales growth, and set competitive prices. Vital for business operations.

Example: 40% markup on $50 cost = $70 selling price

Tips & Service

Calculate appropriate tips for restaurants, delivery services, and other service industries. Split bills among friends easily.

Example: 18% tip on $75 bill = $13.50 tip amount

Essential Percentage Formulas

Calculation Type Formula When to Use
Basic Percentage Result = (Percent/100) × Value Finding X% of a number
Percentage Increase New = Original × (1 + Percent/100) Price hikes, salary raises, growth
Percentage Decrease New = Original × (1 - Percent/100) Discounts, depreciation, loss
Find Percentage Percent = (Part/Whole) × 100 Test scores, market share, ratios
Percentage Difference % Diff = |(A-B)/[(A+B)/2]| × 100 Comparing two values

Common Percentage Equivalents

25%
¼ or 0.25
50%
½ or 0.5
75%
¾ or 0.75
10%
1/10 or 0.1
20%
1/5 or 0.2
33.33%
⅓ or 0.333

Frequently Asked Questions (FAQ)

How do I calculate percentage increase?

To calculate a percentage increase: New Value = Original × (1 + Percentage/100). For example, a 20% increase on $100: $100 × (1 + 20/100) = $100 × 1.20 = $120. The increase amount is $20.

What's the difference between percentage points and percent?

Percentage points measure absolute change (e.g., from 10% to 15% is a 5 percentage point increase). Percent change measures relative change (from 10% to 15% is a 50% increase). Our calculator handles both types of calculations correctly.

How do I add or subtract percentages correctly?

Adding percentages: Convert to decimals first. 20% + 30% = 0.20 + 0.30 = 0.50 (50%).
Sequential percentages: Multiply, don't add. A 20% discount then 10% off: $100 × 0.80 × 0.90 = $72 (not $70). Our calculator handles sequential calculations correctly.

What is reverse percentage calculation?

Reverse percentage finds the original value before a percentage change. If you know the final value and percentage change: Original = Final / (1 ± Percentage/100). Example: Final price $88 after 12% discount: Original = $88 / (1 - 0.12) = $100.

How accurate is this percentage calculator?

Our calculator uses precise decimal arithmetic with up to 8 decimal places of accuracy, matching financial and scientific standards. All calculations follow proper mathematical order of operations and handle edge cases correctly (like division by zero).