A “30% off” label tells you the percentage reduction, not the exact amount you will pay. The arithmetic is easy once you know the original price. You can use the same formulas for shopping, invoices and planning promotions.
The two basic discount formulas
Final price = original price − discount amount
For an item marked at ₹1,000 with a 20% discount, the reduction is ₹1,000 × 0.20 = ₹200. The customer pays ₹800 before any additional taxes, shipping or fees that may apply.
Quick examples you can check yourself
| Original | Discount | You save | New price |
|---|---|---|---|
| ₹500 | 10% | ₹50 | ₹450 |
| ₹1,000 | 20% | ₹200 | ₹800 |
| ₹2,000 | 25% | ₹500 | ₹1,500 |
| ₹1,500 | 30% | ₹450 | ₹1,050 |
| ₹800 | 50% | ₹400 | ₹400 |
These are arithmetic examples, not current prices at any retailer. The same formulas work with other currencies.
How to find the discount percentage from two prices
If a ₹1,200 item now costs ₹900, the savings are ₹300. Divide ₹300 by ₹1,200 and multiply by 100: the reduction is 25%. This only works when the stated original price is genuine; the arithmetic cannot verify a store's pricing claims.
Why two discounts don't simply add together
Suppose a ₹1,000 item gets 20% off, then another 10% off the already reduced price. After the first discount it costs ₹800. The second discount is 10% of ₹800, or ₹80, leaving ₹720. Total savings are ₹280, equivalent to 28% of the original—not 30%.
What about tax and delivery?
Check whether a displayed price already includes tax, whether delivery charges apply, and whether a coupon has eligibility conditions. A discount on the product price does not necessarily reduce every part of the final checkout total.
Check the result without mental math
Enter the original price and percentage in the Manglo discount calculator. If you're selling rather than buying, add your product cost to estimate what remains after the reduction. For a fuller estimate including other expenses, use the profit calculator.
One small next step.
Use Manglo's free toolkit to put the ideas in this guide into practice. No sign-up required.
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