Free tool · DOOH CPM
DOOH CPM Calculator
Digital out-of-home is priced on two levels at once — what you pay for screen time, and how many people that screen time reaches. Enter your media spend, the number of ad plays, and the average audience per play to convert it all into a CPM you can compare against any other channel.
DOOH is priced twice — screen time and the crowd in front of it
A billboard vendor quotes you for plays or for a slot. Your CFO and your client think in CPM. The gap between those two languages is where DOOH budgets get mispriced.
Plays are not impressions
A screen can loop your creative thousands of times in a day, but a play is only an impression once a real person is in front of it. Multiplying plays by average audience is the step that turns a media-side metric into an audience-side one.
Audience figures are estimates
Out-of-home reach comes from traffic counts, footfall sensors, or mobile-location panels — not server logs. Treat the audience-per-play number as a measured estimate and ask the vendor how it was derived before you trust the CPM.
Compare it like-for-like
A DOOH CPM is only useful next to the CPM of the channels you would otherwise buy. Hold the audience definition steady and benchmark within a market — a $12 transit-screen CPM and a $12 social CPM are not buying the same attention.
Calculate your DOOH CPM
Enter media spend, ad plays, and average audience per play.
Total amount paid (or quoted) for the screen time on this buy.
Number of times your creative plays across the screens.
Average people who see one play.
Waiting for input
Enter media spend, ad plays, and average audience per play to see your DOOH CPM.
Impressions = plays × avg audience. CPM = spend ÷ impressions × 1,000.
What is DOOH CPM?
DOOH CPM is the cost to deliver one thousand impressions on digital out-of-home screens — billboards, transit displays, retail and place-based networks. Because DOOH is sold on screen time rather than per impression, you first convert plays into impressions, then express the cost per thousand.
Stating the buy as a CPM is what makes out-of-home directly comparable to display, video, social, and CTV. It normalises a play-based, location-based medium onto the same cost-of-attention scale every other channel already uses.
Impressions from plays
Impressions = Ad plays × Avg audience per play
40,000 plays × 25 avg audience = 1,000,000 impressions
Calculate DOOH CPM
CPM = (Media spend ÷ Impressions) × 1,000
Spend $12,000 for 1,000,000 impressions → CPM = (12,000 ÷ 1,000,000) × 1,000 = $12.00
Cost per play
Cost per play = Media spend ÷ Ad plays
$12,000 ÷ 40,000 plays = $0.30 per play
How to use this DOOH CPM calculator
Three inputs — what you paid, how often it ran, and who saw each run.
Enter your media spend
Use the all-in cost for the screen time on this buy. If production or data fees are separate line items, decide up front whether to include them so your CPM stays comparable across vendors.
Add plays and average audience
Take the number of times your creative loops from the proposal, and the average audience per play from the vendor’s measurement source. The product of the two is your impression base.
Compare the CPM, not the headline price
Read the resulting CPM against the other channels competing for the same budget. A low cost per play can still be an expensive CPM if the screen barely reaches anyone.
What is the difference between DOOH CPM and standard CPM?
The formula is identical — cost divided by impressions, times a thousand. The difference is how you get to impressions. Standard digital CPM counts served impressions directly, while DOOH starts from screen plays and multiplies by an estimated audience per play to reach an impression count.
How is the audience per play measured?
Out-of-home vendors estimate audience from traffic and footfall data, camera or sensor counts, and mobile-location panels, often following an industry measurement standard for the market. It is an estimate, not a log, so ask which methodology a quote uses and whether the figure is total passers-by or those likely to actually see the screen.
Why is cost per play useful if CPM is the comparable metric?
Cost per play tells you what each loop of your creative costs, which is how DOOH inventory is usually bought and negotiated. CPM is what makes the buy comparable to other channels. Looking at both keeps you fluent in the vendor’s language and your media plan’s language at the same time.
Is a lower DOOH CPM always the better buy?
No. As with any CPM, a low number against the wrong location or a thin audience wastes budget efficiently. Weigh CPM against the relevance of the location, dwell time in front of the screen, and how the audience matches your target before optimising purely for the cheapest impressions.
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