Percentage Calculator

Basic Percentage Calculator

Our Basic Percentage Calculator helps you find what percentage of a number equals another number.

1. Enter the percentage in the first field
2. Enter the value in the second field
3. Click "Calculate" to see what that percentage of your value equals

Find Percentage Calculator

This calculator determines what percentage one number is of another.

1. Enter the number you want to find the percentage for
2. Enter the total value
3. Click "Calculate" to see what percentage the first number is of the total

Percentage Increase/Decrease Calculator

This tool calculates the percentage change between two values.

1. Enter the original value in the "From" field
2. Enter the new value in the "to" field
3. Click "Calculate" to see the percentage increase or decrease

What is a Percentage?

A percentage is a way to express a number as a fraction of 100. The word "percent" comes from the Latin "per centum," meaning "by the hundred." Percentages are used to express how large one quantity is in relation to another quantity.

The percentage symbol % is derived from the Italian word "per cento," which means "for a hundred." It's a convenient way to compare values and express proportions.

Common Percentage Formulas

Here are some common percentage calculations that you might need:

• Finding a percentage of a number: (Percentage × Number) ÷ 100
• Finding what percentage one number is of another: (Number ÷ Total) × 100
• Finding the percentage increase or decrease: ((New Value - Original Value) ÷ |Original Value|) × 100
• Finding the original number when a percentage is given: Final Number ÷ (1 + Percentage ÷ 100)

Real-World Applications of Percentages

Percentages are used in various real-world scenarios:

• Finance: Interest rates, discounts, taxes, and return on investments
• Business: Profit margins, growth rates, and market share
• Education: Test scores and grade calculations
• Statistics: Data analysis and comparison
• Health: Body fat percentage, nutritional information, and medical dosages

Mental Math Shortcuts

Here are some shortcuts to calculate percentages quickly:

• Finding 10%: Simply move the decimal point one place to the left. For example, 10% of 250 is 25.0.
• Finding 1%: Move the decimal point two places to the left. For example, 1% of 250 is 2.5.
• Finding 5%: Calculate 10% and then divide by 2. For example, 5% of 250 is 12.5.
• Finding 25%: Divide by 4. For example, 25% of 250 is 62.5.
• Finding 50%: Divide by 2. For example, 50% of 250 is 125.

Common Percentage Errors to Avoid

Be careful to avoid these common mistakes when working with percentages:

• Confusing percentage points with percentages: An increase from 10% to 15% is a 5 percentage point increase, but a 50% relative increase.
• Forgetting the base value: When calculating percentage change, always use the original value as the denominator.
• Adding percentages directly: If an item increases by 10% and then by another 10%, the total increase is not 20% but 21% (1.1 × 1.1 = 1.21).