Percentage Calculator

Perform common percentage operations: find a percentage of a value, calculate what percentage one number is of another, and find percentage change.

Scratchpad (not saved)

Save to create a persistent, shareable workspace.

What This Calculator Does

Handle common percent math in one place, including percent of a number, percentage point differences, and relative change from an original value.

It combines Value, Percentage, Second Value to estimate Percentage of Value, Value Increased by Percentage, Value Decreased by Percentage.

Formula & Method

Core formulas are x\%\text{ of }V = V\cdot\frac{x}{100}, V\text{ is }x\%\text{ of }B \Rightarrow B=\frac{V}{x/100}, percentage change \Delta\% = \frac{V_2-V_1}{|V_1|}\times100, increase V_{inc}=V\left(1+\frac{x}{100}\right), and decrease V_{dec}=V\left(1-\frac{x}{100}\right).

Notation used in the formulas: R = Percentage of Value; x_{1} = Value; x_{2} = Percentage; x_{3} = Second Value.

Method summary: inputs are normalized to consistent units, core equations are evaluated, then secondary values are derived and rounded for display.

Use this for discounts, price adjustments, KPI movement, and any workflow where percent comparisons need to be precise and quick.

Inputs Used

Value: The base value
Percentage: The percentage to calculate with
Second Value: The new value for percentage change calculation (leave 0 to skip)

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