What counts as scarcity messaging
This collection covers low-stock lines under the Add to Cart button, "selling fast" labels, % sold progress bars, and stock-level copy in the buy box.
Countdown timers have their own countdown timer hub.
The win/loss record
7 wins, 0 losses recorded. Six tests added or strengthened scarcity, and one removed it. The removal produced the largest percentage lift.
Where scarcity was tested
- Product page: 6
- Checkout: 1
Biggest wins and their numbers
Adding or sharpening scarcity
- Dave Diederen's "Selling Out Fast" banner with % sold bar and countdown: +8.04% CVR, +8.83% RPV, AOV unchanged
- Dave's bundle selector title changed from "Buy More, Save More" to "Low Stock - Selling Fast": +2.32% CVR, +4.82% RPV
- Dave's "Low stock" changed to "Low stock - selling fast" under Add to Cart: +2.90% CVR, +2.50% RPV
- Oliver Kenyon's authentic scarcity messaging on product pages: +$46,900 per month
- Oliver's brand-aligned scarcity text below Add to Cart: $44,751 per month forecast
- Kasper Dolk's trust and urgency elements on a Plus checkout: +$33,435
Oliver Kenyon describes both wins as authentic or brand-aligned scarcity, which is the common thread: real stock levels, written in the store's voice.
Removing scarcity
Dave Diederen's "In Stock" test gained +16.78% RPV, +5.72% CVR and +10.46% AOV.
The post doesn't explain why the reassuring version won.
@oliverkenyon@oliverkenyon
@DaveDiederen@DaveDiederen@DaveDiederen@DaveDiederenTests that lost or were flat
None were recorded. The "In Stock" result is the closest thing to a loss for scarcity, since the control was the scarcity message.
Design patterns that won
- One short line under Add to Cart or in the buy box.
- "Selling fast" framing rather than a bare "Low stock".
- Real stock, in the brand's tone.
- A visual % sold bar when paired with a real sale.
Ideas not yet measured
The 25 ideas include Kasper Dolk's "Only X left at this price" line under sizes and a "1 of 50" limited-edition badge, and Dave Diederen's stock tracker that turns orange under 10 units.
Josh Thompson's low-stock counter ideas come with claimed results but no test data.
How to add scarcity messaging on Shopify
Most themes have an inventory or stock-level block in the product template that shows a message below a set quantity.
Edit the copy there, or use an app for % sold bars. Only show stock levels that are true.
How to test it on your store
Hypothesis: a short, honest "selling fast" line under Add to Cart will raise conversion.
If you already show low-stock warnings, also test "In Stock" against them.
Measure revenue per visitor and AOV, and size it with the sample size calculator.