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Best of 2026

Best Free Percentage Calculator

Percentage calculations come up everywhere — shopping discounts, grade calculations, investment returns, tip calculations, and more. A great percentage calculator should handle ALL types of percentage problems, show the formula, and give instant results.

Our Top Picks

  1. 1
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    Percentage Calculator

    Solves all 4 types of percentage problems: what is X% of Y, what percent is A of B, percentage increase/decrease, and percentage difference.

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  2. 2
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    Discount Calculator

    Apply any discount percentage and see the final price. Stack multiple discounts and add sales tax.

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  3. 3
    📚

    Grade Calculator

    Calculate your grade percentage and see what you need on the final exam.

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  4. 4
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    Margin Calculator

    Calculate profit margin percentage from cost and selling price.

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Pro Tips

  • ✓To find 15% of anything: find 10% (move decimal left), find 5% (halve that), add them together
  • ✓Percentage increase and decrease are NOT symmetrical — a 50% increase then 50% decrease leaves you at 75%, not 100%
  • ✓To convert a fraction to a percentage, divide numerator by denominator and multiply by 100

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