Discount Calculator

Work out a sale price in one step. Enter the original price and the discount percentage, and this shows the final price and exactly how much is saved.

Free vs paid — when to upgrade

What this free tool is great for: a quick, one-off job with no signup — it runs entirely in your browser, so nothing leaves your device and there's nothing to manage.

Its honest limit: it's a one-off calculation in your browser — it doesn't save your scenarios, update as your real numbers change, or connect to your live accounts, so you re-enter the figures every time and can't watch how they move.

Where Sellfy does more: Running discounts to drive sales? An all-in-one store like Sellfy lets you sell digital and physical products and run discount codes without the hassle.

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A discount costs your margin, not your price

The most important thing to understand about discounts is that they come out of profit, not revenue — and because profit is only a slice of the price to begin with, the damage is far larger than the discount percentage suggests. Knock 20% off a price and you haven't given away a fifth of your profit; depending on your margin, you may have given away most of it, or all of it. This calculator shows you the real numbers, but the mindset shift is the point: a discount is a decision to hand a chunk of your hard-won margin to a customer, and it should be made as deliberately as any other spend.

Why the psychology is so seductive

Discounts work on buyers because they trigger a sense of urgency and a feeling of winning. A price that was higher and is now lower feels like a gain, even if the "before" price was set precisely to make the discount look good. This is powerful, and used well it genuinely drives sales. But it cuts both ways: the same psychology that pulls customers in also trains them, over time, to distrust your full price and to wait for the next sale. The seductiveness is exactly why discounts need discipline — the tactic that lifts this month's numbers can quietly erode your pricing power for years.

Percentage, fixed and buy-one-get-one

Discounts come in several shapes, and they land differently. A percentage off feels bigger on expensive items and is easy to grasp. A fixed amount off feels bigger on cheap items and can be more controllable. Buy-one-get-one and threshold offers ("spend X, save Y") nudge basket size and can protect margin better than a straight discount because they require the customer to buy more. Each shifts customer behaviour in a particular direction, so the right format depends on what you're trying to achieve — clearing stock, raising order value, or winning a first purchase — not just on which number sounds most generous.

Anchoring and the "was / now" tactic

The reason a struck-through original price sits next to the sale price is anchoring: the high number sets the reference point that makes the low one feel like a bargain. It's one of the most reliable tools in retail, and entirely legitimate when the anchor is a real, genuinely-charged price. It becomes dishonest — and in many places illegal — when the "was" price was never really charged, or was inflated purely to fake a discount. For a brand built on trust, the line matters: anchor against real prices, and the tactic builds sales without costing credibility. Fake the anchor and you win a sale while quietly teaching customers not to believe you.

When discounts help — and when they hurt

Discounts have genuinely good uses: clearing slow or seasonal stock, acquiring a first-time customer who'll return at full price, rewarding loyalty, or hitting a specific short-term target. They turn destructive when they become routine — a predictable monthly sale teaches customers to never buy at full price, permanently resetting their reference point downward. The test is whether the discount is a deliberate, bounded tactic or a crutch you keep reaching for because full-price sales have stalled. The former is smart marketing; the latter is a slow-motion price cut you're making without admitting it, and it's very hard to reverse once customers expect it.

The margin maths you must run first

Before any discount, run the number that matters: how much extra volume you need just to break even on the promotion. Because the discount comes out of margin, a business with a thin margin needs a huge sales uplift to come out ahead, while a high-margin business has more room. Often the required uplift is far larger than people assume — a discount that feels modest can demand you sell dramatically more units just to make the same profit. If the realistic sales bump won't clear that bar, the discount loses money even as it looks busy. This single calculation prevents most discount decisions that feel good and lose money.

Depth versus frequency

Two dials control a discount strategy: how deep the discount is, and how often you run it. Deep but rare (a genuine annual clearance) preserves your full-price positioning while creating a real event. Shallow but constant erodes margin quietly and, worse, normalises the discounted price as the "real" price. Frequency is the more dangerous dial, because customers learn patterns fast — if there's always a sale on, there's effectively no full price. Guarding frequency, even more than depth, is how premium and mid-market brands keep their pricing power while still using promotions when it counts.

Measure the ROI, don't just feel it

A discount that "did well" because sales spiked may still have lost money once you account for the margin sacrificed and the customers who'd have bought anyway at full price. The honest measure isn't the sales bump — it's the incremental profit: the extra margin from genuinely new sales, minus the margin given up on sales you'd have made regardless. That's a harder number to face, and it's why so many businesses keep discounting on gut feel. Treating each promotion as an experiment with a measured profit outcome, rather than a reflex, is what turns discounting from a margin leak into a real tool.

Running promotions on your own store — where Sellfy does more

This calculator tells you what a discount really costs and how much you'd need to sell to justify it — the analysis every promotion deserves before it runs. Actually running those promotions — setting up discount codes, limited offers, upsells and a storefront that sells your products — is a separate job. That's where a platform like Sellfy does more: it gives creators and small businesses a store with built-in discount codes, promotions and checkout, so you can put the pricing decisions you've modelled here into practice. Use this tool to decide whether a discount is worth it; use a store platform to run it without wiring the mechanics together yourself.

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