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General Calculators

Percentage Increase / Decrease Calculator

Calculate percentage increase or percentage decrease between two numbers with step-by-step resolution.

Percentage Increase
+50%

Absolute change of +25

Step-by-Step Mathematical Resolution:

  • Step 1: Calculate the absolute change: |75 - 50| = 25
  • Step 2: Divide the change by original value: 25 / |50| = 0.5000
  • Step 3: Multiply by 100 to convert to percentage: 0.5000 × 100 = 50.00%
  • Result: A 50.00% increase.

Percentage Increase & Decrease Formula

Calculates the relative percentage change between an initial original value and a final revised value, identifying whether it represents growth or reduction.

Percentage Change = [ (Final Value - Initial Value) / |Initial Value| ] * 100

Calculation Steps

  • 1Subtract the initial value from the final value to find the absolute difference.
  • 2Divide the difference by the absolute initial value.
  • 3Multiply by 100 to convert into percentage.
  • 4A positive result indicates a Percentage Increase; a negative result indicates a Percentage Decrease.

Practical Example

Scenario: Score increased from 64 marks in test 1 to 80 marks in test 2

Inputs: Initial Value: 64 | Final Value: 80

Calculation: Difference = 80 - 64 = +16. Percentage Change = (16 / 64) * 100 = +25.00%

Result: Percentage Increase: +25.00%

Assumptions & Disclaimers

Key Assumptions:

  • Initial value cannot be zero (percentage change from zero is undefined).
  • Both values share identical units.

Percentage changes are asymmetric: a 50% increase followed by a 50% decrease results in a net 25% drop from the original value.

Frequently Asked Questions

Percentage Decrease = ((Original Value - New Value) / Original Value) * 100.

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