math calculator
Solve percentage changes, ratios, and differences.
Save this page to solve ratios, discounts, markups, or tax rates on the go.
Percentage result
36
Formula
Percent of = percent / 100 x value; Change = (new - old) / |old| x 100The calculator supports percent of a value, percent change, and percent difference.
Step by step
Example
15% of 240 is 36, and a change from 200 to 250 is a 25% increase.
Related guides
Guide
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Summary
Calculated Part
36
Percentage Used
15%
Base Whole Value
240
D3 visualization
Visual breakdown showing the calculated percentage part against the remaining base value.
D3 visualization
Comparing the base whole value against the calculated percentage part.
Guide
Percentages represent a fractional part of 100, which makes comparing ratios of different sizes straightforward. This tool simplifies everyday and mathematical percentage calculations by separating them into three distinct operations.
The first mode calculates a basic percent of a value, the second determines percentage change (increase or decrease) between two numbers, and the third finds the percent difference between two values.
To find the percent of a number: divide the percentage by 100 and multiply by the base value.
To calculate percentage change: subtract the original value from the new value, divide by the absolute original value, and multiply by 100. Positive values indicate an increase, while negative values indicate a decrease.
Ratio
The quantitative relation between two amounts showing the number of times one value contains or is contained within the other.
Relative change
A measure of the change in a variable relative to its starting value, expressed as a fraction or percentage.
Percent change is used when there is an old (starting) value and a new (ending) value, showing the relative increase or decrease. Percent difference compares two numbers of equal status, calculating the absolute difference relative to their average.
Multiply the decimal value by 100 and add the percent symbol. For example, 0.25 becomes 25%.