Double Discount Calculator

Find the real price after two discounts

When two separate discounts stack on the same item, such as fifty per cent off followed by an extra twenty per cent, the combined result is genuinely not seventy per cent off, and the size of that difference surprises almost everyone. This calculator finds the true final price after two stacked discounts, so you know exactly what you will actually pay at the till rather than what the marketing implies.

Why stacked discounts do not add up

The intuitive and extremely common mistake is simply to add the two percentages together, but stacked discounts multiply rather than add, because the second discount is applied to the already-reduced price, not to the original one. So fifty per cent off and then twenty per cent off leaves eighty per cent of fifty per cent, which works out to forty per cent of the original price, a genuine discount of sixty per cent, not the seventy that adding would suggest. Understanding this stops you overestimating the saving, and it lets you correctly compare a stacked offer against a single larger discount to see which is genuinely better value.

The true saving

The calculation runs entirely in your browser, so your figures are never uploaded and stay on your own machine, which matters for anything involving money and personal finances.

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