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Discount calculator

Calculate final price after discount and savings.

Enter price and discount.

Discount Calculator Guide

Types of discounts: There are percentage discounts (e.g., 20% off), fixed amount discounts (a constant reduction, e.g., $50 off), and quantity discounts (for larger purchases - the more you buy, the bigger the discount). There are also seasonal discounts (e.g., winter sales), promotional discounts (linked to marketing campaigns), and loyalty discounts for regular customers.

Calculation formulas: Percentage discount: discount amount = original price × (discount / 100). Price after discount = original price - discount amount. With fixed amount discount: price after discount = original price - fixed amount. With multiple discounts (e.g., 20% + 10%), note: the second discount is calculated from the price after the first discount, so it's not equivalent to 30% off.

Seller pricing strategies: Sellers often use psychological pricing tricks: prices ending in .99 (e.g., $99.99 seems cheaper than $100), discounts presented as "save $X" rather than as a percentage, "buy 2, get 1 free" promotions (often more expensive than a simple discount), inflated prices before promotions.

How to shop smart: Always compare pre-promotion prices with current prices - sometimes "discount" is actually the market price. Check prices across different stores as promotions vary between sellers. Pay attention to minimum purchase amounts for discounts. Calculate actual savings - don't be fooled by large percentages on small amounts.

Why stacked discounts are smaller than they look

Percentages off do not add. A 20% discount followed by a further 20% is not 40% — it is 36%, because the second reduction applies to the already-reduced price. That gap is where most till-side confusion lives.

How it works

  • Applies each discount in sequence to the running price, rather than summing the percentages.
  • Shows the amount saved and the effective single discount the sequence is equivalent to.
  • Handles a fixed amount off alongside a percentage, where order changes the result.
final = original × (1 − d1) × (1 − d2) × ...

effective discount = 1 − (1 − d1)(1 − d2)

20% then 20%  → 1 − 0.8 × 0.8 = 36%   (not 40%)
50% then 50%  → 1 − 0.5 × 0.5 = 75%   (not 100%)
30% then 10%  → 1 − 0.7 × 0.9 = 37%

Worked example

A 200 coat advertised at 30% off, with a further 15% staff discount at the till.

  1. 200 × (1 − 0.30) = 140
  2. 140 × (1 − 0.15) = 119
  3. total saved = 200 − 119 = 81
  4. effective discount = 81 ÷ 200 = 40.5%, not 45%

You pay 119, saving 81. The two discounts feel like 45% but deliver 40.5% — a difference of 9 on this purchase, and the gap widens as the percentages get larger.

Reading the result

  • Order does not matter for percentages, but it does matter when a fixed amount is involved. A 20 voucher applied before a 25% discount saves you less than the same voucher applied after — check which the shop does.
  • A discount off an inflated 'was' price is not a discount. The reference price is what matters, and in many jurisdictions retailers must show the lowest price charged in the preceding 30 days for exactly this reason.
  • Compare the final price against other shops, not the percentage against other offers. 40% off an expensive baseline routinely beats 60% off nothing.
  • For VAT-inclusive pricing, the discount applies to the gross amount, so the VAT falls proportionally too. You do not save the VAT separately.

Common questions

Is 20% off then another 20% the same as 40% off?
No. It is 36%. The second discount applies to 80% of the original, so you get 20% of 80% rather than 20% of 100%. The larger the individual discounts, the wider the gap: 50% twice gives 75%, not 100%.
Does the order of discounts change what I pay?
Not for two percentages — multiplication is commutative. It does change things when a fixed-amount voucher is mixed in: applying the voucher last, after the percentage, always saves you more.