Add or Subtract Percentage Calculator
Quickly add or deduct a percentage from any base number with verified arithmetic proofs.
Add a percentage
Subtract a percentage
Decimal multiplier shortcuts
Instead of finding the percentage amount and then manually adding or subtracting it, use a direct multiplier:
To add P%
For example, adding 8% tax means multiplying by 1.08.
To subtract P%
For example, a 25% discount means multiplying by 0.75.
Frequently asked questions
How do you add a percentage to a number?
Multiply the number by (1 + Percentage ÷ 100). For example, to add 15% to $100: $100 × (1 + 0.15) = $100 × 1.15 = $115.
How do you subtract a percentage from a number?
Multiply the number by (1 − Percentage ÷ 100). For example, to discount $100 by 20%: $100 × (1 − 0.20) = $100 × 0.80 = $80.
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