Percentage Calculator

Smart 3-field calculator: fill any 2 fields to automatically calculate the 3rd. Perfect for discounts, taxes, and percentage changes.

Start Value

Final Value

Percentage

Mode:

Common Calculations

Formula: Final Value = Start Value × (1 + Percentage ÷ 100)

Example: $100 increased by 25% = $100 × 1.25 = $125

Formula: Final Value = Start Value × (1 - Percentage ÷ 100)

Example: $100 decreased by 25% = $100 × 0.75 = $75

Formula: Final Value = Value × (Percentage ÷ 100)

Example: What is 25% of 200? = 200 × 0.25 = 50

Formula: Percentage = ((Final Value - Start Value) ÷ Start Value) × 100

Example: Change from 80 to 100 = ((100 - 80) ÷ 80) × 100 = 25%

Fill any 2 fields and the calculator automatically computes the 3rd. No need to click "Calculate" - just start typing!