Solve every common percentage calculation with 5 specialized modes: percent of a number, percentage increase or decrease, part-to-whole proportions, retail discounts with sales tax, and reverse percentages with step-by-step mathematical explanations.
Intuitive, friction-free workflow designed to get you from input to accurate results in seconds.
Select your calculation mode from the top toolbar tabs.
Enter your values into the designated input fields or click quick percentage chips (e.g. 15%, 20%, 50%).
Read the bold primary result and plain-English summary immediately.
Review the Step-by-Step Formula breakdown below to see the exact mathematics behind your answer.
Consult the Quick Reference Table to see common percentage benchmarks for your base number.
Click 'Copy Result' to copy the calculated value to your clipboard.
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Retail discounts, tax calculations, tip splitting, grade percentages and growth rates all boil down to the same math with different framing. What is 15% off 79.99? What percent is 42 of 160? Did revenue grow or shrink quarter over quarter?
Mental math on percentages introduces rounding errors that compound in spreadsheets. A dedicated calculator gives exact figures you can paste into invoices, reports and presentations with confidence.
Straightforward answers regarding percentage calculator calculations, platform limits, and data privacy.
Subtract the old value from the new value, divide by the absolute value of the original, and multiply by 100: ((To - From) / |From|) * 100. A positive result represents an increase, while a negative result represents a decrease.
Enter the original retail price and the discount percentage. The tool calculates your cash savings and discounted price. If your region has sales tax, enter the tax percentage to see the final post-tax checkout total.
Reverse percentage finds the original 100% base value when you only know a portion and its percentage. For example, if $75 represents 30% of a budget, the reverse formula (75 / 0.30) reveals the full budget was $250.
Yes. If an investment grows from $100 to $300, it experienced a 200% increase (+200%). Similarly, a quantity can be more than 100% of a base (e.g. 150% of 80 is 120).
Mathematically, dividing by zero is undefined. If a starting value was 0 and became 10, the absolute increase is 10, but the percentage growth cannot be expressed as a finite ratio.
Results are displayed with up to two decimal places for clean currency and measurement display, using exact decimal arithmetic internally.
In-depth articles and tutorials to get the most out of Percentage Calculator.
Learn how to calculate retail sales tax, restaurant tip percentages, and reverse tax amounts. Discover step-by-step formulas and fast mental math rules.
Master percentage calculations for business, retail discounts, and financial growth. Learn the exact percentage change formula with step-by-step worked examples.
Calculate original values before discounts or sales taxes. Master the simple division formula to find pre-discount prices and reverse VAT in seconds.
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