Free Online Maths Calculators

Maths calculators can save time when solving everyday numerical problems. Instead of manually working through a formula, you can enter the values you know and let the calculator perform the arithmetic.

Easy Calculator provides tools for some of the most common maths tasks, including percentages, percentage change, fractions, ratios and scientific calculations.

How Do You Calculate a Percentage?

A percentage represents a value as a fraction of 100. One of the most common calculations is finding a percentage of another number.

The general formula is:

Percentage of a Number = Number × Percentage ÷ 100

For example, to calculate 20% of 250:

250 × 20 ÷ 100 = 50

Therefore, 20% of 250 is 50.

How Do You Find What Percentage One Number Is of Another?

To determine what percentage one value represents of another, use:

Percentage = Part ÷ Whole × 100

For example, if 30 people out of a group of 120 selected an option:

30 ÷ 120 × 100 = 25%

The Percentage Calculator can perform these calculations automatically.

Percentage Increase and Decrease

Percentage change measures how much a value has changed relative to its original amount.

A common formula is:

Percentage Change = (New Value − Original Value) ÷ Original Value × 100

A positive result represents an increase, while a negative result represents a decrease.

Percentage Increase Example

Suppose a price increases from $80 to $100.

The increase is:

$100 − $80 = $20

Then:

$20 ÷ $80 × 100 = 25%

So the price increased by 25%.

Percentage Decrease Example

Suppose a value falls from 200 to 150.

The change is:

150 − 200 = −50

Then:

−50 ÷ 200 × 100 = −25%

This represents a 25% decrease.

How Do Fractions Work?

A fraction represents part of a whole and is usually written using a numerator and denominator.

For example:

3/4

Here, 3 is the numerator and 4 is the denominator.

Fractions can be added, subtracted, multiplied or divided, but addition and subtraction generally require a common denominator.

Adding Fractions

For fractions with the same denominator:

2/7 + 3/7 = 5/7

For fractions with different denominators, a common denominator usually needs to be found first.

Multiplying Fractions

To multiply fractions, multiply the numerators together and the denominators together.

For example:

2/3 × 4/5 = 8/15

What Is a Ratio?

A ratio compares two or more quantities. Ratios are commonly written using a colon.

For example:

2:4

This ratio can be simplified by dividing both values by 2:

1:2

Ratio calculations are useful in recipes, maps, scale drawings, construction, finance and many everyday calculations.

Scientific Calculator

A scientific calculator extends beyond basic addition, subtraction, multiplication and division. Depending on the tool, scientific calculations can include powers, square roots, logarithms, trigonometric functions and brackets.

Scientific calculators are commonly used in mathematics, science, engineering and education.

Which Maths Calculator Should I Use?

• Use the Percentage Calculator to find a percentage of a number or determine what percentage one value is of another.
• Use the Percentage Change Calculator to calculate percentage increase or decrease.
• Use the Fraction Calculator to add, subtract, multiply or divide fractions.
• Use the Ratio Calculator to simplify or compare ratios.
• Use the Scientific Calculator for more advanced mathematical operations.