Rounded vs Precise Discounts: which sells best?

Reading time: 4 min

Research-Based Insight

The ideas below are based on controlled academic experiments. Real-world results may vary depending on your product, audience, and context. Think of this as a tested nudge, not a guaranteed conversion hack. (source: Can rounding up price discounts reduce sales?” Journal of Consumer Psychology, Sept 2023. Authors: Jha, Biswas, Guha, Gauri)

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Let me hit you with a gut-punch marketing truth: that shiny, rounded-up discount you’re flashing all over your store—like “8% Off”—might actually be costing you sales. I know, it sounds backward. Bigger number, better deal, right?

Wrong.

According to a recent peer-reviewed study published in the Journal of Consumer Psychology, researchers ran multiple experiments testing whether rounding up price discounts would improve or hurt performance. Their hypothesis was that consumers should prefer higher, simpler numbers—like “8%” over “7.7%.” After all, it sounds like more value, right?

Turns out, the exact opposite happened. Time after time, shoppers preferred the precise, slightly smaller discount. In one experiment, participants were shown two discount messages: “Save 7.7%” versus “Save 8%.” The researchers measured purchase intention and perceived urgency. The result? More people said they’d buy when shown the 7.7% discount. The intention-to-purchase score was statistically higher—even though the savings were technically smaller.

And it wasn’t a one-off. The researchers repeated this experiment across different product categories (from everyday household goods to larger-ticket items), different price ranges, and different discount formats—flat dollar and percentage off. In each case, precision increased effectiveness.

So why does this work?

The study digs into something called perceived temporal availability. That’s a mouthful, but here’s what it means in plain English: People look at a discount and unconsciously estimate how long it’ll be available. When they see a nice, round number like 8% or 10%, they think, “Eh, this’ll probably be here next week.”

But when they see 7.7%, that specificity hits differently. It feels fresh. Temporary. Like it was calculated this morning by someone in marketing who might yank it down tomorrow. That subtle psychological cue triggers a sense of urgency. “Act now… before it disappears.”

The authors even tested this directly. They asked people to rate how long they thought the discount would last. Rounded discounts were seen as lasting longer. Precise discounts? Shorter—more limited-time. And limited-time means scarcity, which means higher motivation to buy.

That’s the kicker. You’re not just showing a number—you’re sending a signal.

So what should you do with this?

Stop rounding your discounts just to make the math pretty. Mess it up. Use decimal percentages that sound real, raw, even slightly awkward. Try 11.3% instead of 12%. 6.8% instead of 7%. 9.9% instead of 10%. These “imperfect” numbers outperform perfect ones because they feel honest. Deliberate. Limited. Scarce.

And if you're wondering, “Does this only work for percentages?”—the answer’s no. The research also tested dollar-off amounts. People were more likely to engage with a €19.75 discount than a clean €20 off. Same logic applies: precise numbers = perceived realism and urgency.

Now, before you change every promo banner in your store, let’s zoom out for a second. Here’s your disclaimer.

These findings come from controlled experiments, with variables carefully managed. That means real-world results might vary based on your audience, your brand tone, your product pricing, and your marketing medium. This tactic worked especially well for moderate discounts—in the 5% to 15% range. For massive markdowns, like 50% or 70% off, this trick might get lost in the noise.

It’s also important to note: this isn’t a silver bullet. Precision won’t sell a terrible offer. But if you’ve already got a good product, fair price, and solid positioning, then this simple tweak could turn browsers into buyers—just by adding a decimal point.

To sum it up: numbers are never just numbers. They’re signals. And in a noisy, overloaded market, even the smallest psychological cue—like showing “7.7% off” instead of “8%”—can nudge someone closer to the checkout.

Write it down. Tape it to your desk. Or better yet, etch it into your next pricing campaign:

Don’t round your discounts. Round up your results.