Percentage Calculator – Percent, Discount & Reverse Discount
This Percentage Calculator helps you solve everyday percent problems: what is X% of Y, what percentage one number is of another, percentage increase or decrease, shopping discounts, reverse discounts and even the difference between markup and profit margin.
It is designed to be faster than a basic calculator and easier than remembering multiple formulas, so you can check prices, score changes, profit margins and markups in seconds.
Example: You paid $80 after a 20% discount and want to know the original price before the discount.
See how a 20% markup on cost is different from a 20% profit margin on selling price and what selling price corresponds to each.
What Can You Do With This Percentage Calculator?
This percentage calculator covers almost every common scenario: finding X% of Y, reversing the question to see what percent one value is of another, measuring percentage increase or decrease, and calculating discounts and final prices. It also goes a step further with a reverse discount mode and a markup vs margin mode for small business owners.
Instead of memorising several different percentage formulas, you can simply pick the tab that matches your question, enter the numbers, and get an instant, clearly explained result.
Reverse Discount: Find the Original Price from Sale Price
The reverse discount feature is built for real‑world shopping scenarios. If you know that you paid $80 after a 20% discount, the calculator can work backwards to show the original price before the discount, the discount amount and the effective savings in percentage terms.
This is especially useful when you see “Flat 40% off” or clearance offers and want to check what the store’s original listed prices were before the promotion started.
Markup vs Margin for Small Business
Many small business owners confuse markup and profit margin. A 20% markup on cost is not the same as a 20% margin on selling price, and using the wrong one can lead to under‑pricing or over‑pricing products. The markup vs margin tab lets you enter cost and a percentage and then shows the matching selling price, markup and margin values side by side.
This makes it easier to set prices that cover costs, hit your target profit percentage and still stay competitive in your market.
When Is a Percentage Calculator Useful?
Use this tool when you are checking discounts while shopping, reviewing exam scores, analysing profit or loss, updating prices, or comparing performance metrics across time periods. Having a fast, reliable percentage calculator reduces errors and speeds up decision‑making.
Because it is mobile‑friendly and free of clutter, you can keep it open in a browser tab and use it as your everyday percentage, discount and margin helper.
Percentage Calculator FAQs
A percentage is a way of expressing a number as a fraction of 100. It is commonly used to compare values, show proportions and describe increases or decreases in a format that is easy to read and understand.
Choose the tab that matches your problem, enter the required numbers and press the calculate button. The calculator automatically applies the right formula and shows the result as a percentage, a value or both, along with a short explanation.
Reverse discount mode lets you start from the price you actually paid and the advertised discount percentage to find the original price. This is helpful when you want to compare offers from different stores or understand how big the discount really was.
Markup and margin are related but different. Many business owners think a 20% markup and 20% margin are the same, but they lead to different selling prices. The markup vs margin tab shows both values and the matching selling price so you can price products accurately.
Yes, students often use this calculator to convert marks into percentages, measure percentage improvement between two test scores or check how much a number has changed compared with an earlier value. It supports quick practice and checking of homework.