Cost-per-scan advertising: how CPS compares to CPM and CPC
Cost per scan (CPS) is what you pay each time someone scans your QR code. It sits between CPM, where you pay per thousand impressions, and CPC, where you pay per click. A scan means a real person saw your ad in the physical world and chose to act. Calculate it as total cost ÷ scans, and judge it by what scans turn into.
What is cost per scan?
Cost per scan is the price of one QR code scan, either charged directly per scan or worked out after the fact by dividing what you spent by the scans you got. It's the offline equivalent of a click: proof that someone noticed your ad and took a deliberate action.
Some channels, including Lidquid, bill per scan directly. For anything else with a QR code, such as flyers, posters or packaging, you can calculate an effective CPS yourself and compare channels on the same footing.
How is CPS different from CPM and CPC?
They price different moments in the funnel. CPM pays for exposure, CPC pays for an online click, and CPS pays for a physical-world action.
| Model | You pay for | Where it's used | Main risk |
|---|---|---|---|
| CPM (cost per mille) | 1,000 impressions, estimated or served | Display, social, video, billboards | Paying for views nobody noticed |
| CPC (cost per click) | A click on an online ad | Search, social, display | Accidental and bot clicks |
| CPS (cost per scan) | A scan of a QR code | Stickers, print, packaging, out-of-home | Repeat or self-scans, unless they're verified |
| CPA (cost per acquisition) | A sign-up, sale or booking | Affiliate, performance deals | Fewer partners will take the risk |
Physical ads have traditionally been sold on estimated impressions. QR codes change that, because a scan is a countable event, so physical placements can be bought more like performance media.
How do you calculate cost per scan for a QR campaign?
Add up everything the campaign cost, then divide by the number of scans. Count only unique, genuine scans if your tool lets you, because repeat scans flatter the number.
effective CPS = (printing + placement + QR tool + design + staff time) ÷ unique scans
Include the hidden costs. A free static QR code on a $300 flyer run isn't a $0 campaign. If you paid someone to hand out flyers, that's part of the cost too. When a channel bills per scan, the rate is already your CPS, although you should still count your own creative and landing-page costs.
What does a worked example look like?
Here's an illustrative example with made-up numbers, comparing two hypothetical campaigns for a local gym offering a free first class.
| Illustrative only | Campaign A: flyers | Campaign B: per-scan stickers |
|---|---|---|
| Total cost | $400 | $400 |
| Unique scans | 80 | 200 |
| Effective CPS | $5.00 | $2.00 |
| Scan → free-class booking | 10% | 5% |
| Bookings | 8 | 10 |
| Cost per booking | $50 | $40 |
Campaign B wins on CPS and, in this example, on cost per booking too. Look closer, though: Campaign A's scans converted twice as well. If the stickers had drawn more casual, curiosity-only scans, B could have lost on the number that actually matters. CPS is a starting point, not the finish line.
How do you know if a scan is worth the price?
Work out what a scan is worth to you by multiplying the share of scans that convert by what a customer is worth. If that value is higher than your CPS, the channel pays.
value per scan = conversion rate after scan × customer value
break-even CPS = value per scan
Illustration: if 5% of scans become customers and a customer is worth $120 to you over their first year, each scan is worth about $6. Anything below $6 per scan pays for itself, and anything above it doesn't, before brand effects you can't easily measure.
- Raise conversion with a sharper offer and a faster landing page.
- Raise customer value by sending scans to your best-retaining product or membership.
- Lower CPS with better placement and a hook that earns more scans.
Why do verified, deduplicated scans matter?
Because raw scan counts include noise you shouldn't pay for: the same person scanning twice, the person holding the sticker scanning it to check, and automated traffic. Unfiltered, those inflate your scan count and make your CPS look better than it is.
Lidquid bills only for verified scans: a real person, on a real phone, scanning a sticker for the first time. Repeat scans from the same device, owner self-scans and bots are excluded, and you see raw and billable scans side by side so you can check the filtering yourself. If you're comparing Lidquid with a channel you measure yourself, apply the same rule and count unique scans only, so the comparison is fair.
What mistakes inflate or distort cost per scan?
The most common mistakes are counting raw scans instead of unique ones, leaving costs out, and comparing campaigns over different time periods. Each one makes a channel look better or worse than it really is.
- Counting your own test scans. Every time you or your team checks that the code works, it adds a scan. Exclude them, or test before the campaign starts.
- Ignoring setup costs. Design, printing and tool subscriptions are part of the campaign, even if they were paid separately.
- One code for everything. If the counter, the flyer and the window all share a code, you can't tell which placement worked.
- Stopping at the scan. A cheap scan that never converts costs more than an expensive one that does. Always track the next step.
- Comparing different seasons. Exam week, holidays and the start of term all change behavior, so compare channels over the same weeks.
When is cost per scan the right model?
CPS fits when your ad lives in the physical world and the next step happens on a phone: an app download, a booking, a discount code, a sign-up. It fits poorly when you're buying pure awareness and don't expect anyone to act right away. In that case CPM-style buying, or simply buying the placement, may be more honest about what you're getting.
For most local businesses and apps, a blend works: a small per-scan test to learn your real conversion rate, then more budget behind whichever placements beat your break-even CPS. Our QR sticker marketing playbook covers how to set up that test.