Pick what you are solving for, then enter the two figures you already know.
What the campaign cost you in total.
Times the ad was served, not clicks.
CPM prices attention, not results. Once those impressions turn into orders, check what each new customer actually cost you with the CAC calculator.
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CPM is cost per thousand impressions, the price an advertiser pays for their ad to be shown 1,000 times. The M is not short for million: it is the Roman numeral for a thousand, from the Latin mille. It is the standard way display, video, social and out-of-home inventory is priced.
CPM equals total ad spend divided by impressions, multiplied by 1,000. Spend $500 to earn 250,000 impressions and the sum is 500 divided by 250,000, which is 0.002, then multiplied by 1,000 for a CPM of $2.00. Each individual impression cost you two tenths of a cent.
Multiply the CPM by the impressions you want and divide by 1,000. At a quoted $2.00 CPM, buying 250,000 impressions costs 2.00 times 250,000 divided by 1,000, which is $500. Switch this calculator to Find cost and it does that step for you.
Divide your budget by the CPM and multiply by 1,000. A $500 budget at a $2.00 CPM buys 250,000 impressions, while the same budget at an $8.00 CPM buys only 62,500. This is the calculation worth running before you agree to a rate, because it turns an abstract price into real reach.
It depends almost entirely on the platform and the audience you are targeting. As broad ranges, Facebook and Instagram tend to run around $5 to $12, Google Display around $2 to $5, TikTok around $3 to $10, and LinkedIn far higher at roughly $20 to $60 because you are paying for professional targeting. Treat these as starting points, not targets: your own historical CPM on the same audience is a much better benchmark.
You are paying for who sees the ad, not how many. LinkedIn lets you narrow by job title, seniority, company size and industry, so the pool of matching people is small and every advertiser chasing B2B buyers is bidding for the same impressions. A $40 CPM aimed at 500 decision makers can be far better value than a $4 CPM aimed at everyone.
They price three different things. CPM prices exposure, so you pay per thousand times the ad is shown, whether or not anyone reacts. CPC prices interest, so you pay only when someone clicks. CPA prices outcomes, so you pay per conversion, such as a sale or a signup. Moving from CPM to CPA shifts risk from you to the platform, which is why CPA rates are the most expensive of the three.
No, and this is the most common trap in media buying. Cheap impressions in front of the wrong audience are worthless, and CPM says nothing about whether anyone bought anything. Broad targeting, low quality placements and audience network inventory all push CPM down while pushing cost per purchase up. Judge a campaign on cost per acquisition or return on ad spend, and use CPM to explain why those numbers moved.
Because ad inventory is sold at auction. Between Black Friday and Christmas, nearly every retailer raises their budget at once while the number of people using the platforms stays roughly flat, so more money chases the same impressions and the clearing price goes up. It is normal to see CPM climb 20% to 50% in November against a quiet month, then fall back sharply in January.
Improve creative first, since platforms reward ads people engage with by charging less for them. After that: broaden a targeting set that has become too narrow, refresh creative before frequency climbs and performance decays, test cheaper placements such as Reels or the audience network, and avoid bidding into the busiest weeks if your promotion can wait. Lowering CPM is only a win if conversion rate holds up at the same time.
Impressions count how many times an ad was served, including repeat views by the same person. Reach counts the individual people who saw it at least once. Impressions divided by reach gives frequency, the average number of times each person saw your ad. Two campaigns with the same CPM can behave very differently if one reached 100,000 people once and the other showed the same ad ten times to 10,000 people.
eCPM, or effective CPM, converts any pricing model back into a comparable per thousand figure. If you paid on a cost per click basis and spent $600 for 200,000 impressions, your eCPM is $3.00 even though you never bought impressions directly. Publishers use it to compare revenue across ad units, and advertisers use it to compare campaigns bought on different models.
Not necessarily. An impression usually means the ad was served, which can include ads that loaded below the fold or were scrolled past in a fraction of a second. Viewable impressions are a stricter standard, generally requiring at least half the ad to be on screen for a second or more. If viewability data is available, compare CPM against viewable impressions rather than served ones.
Yes. No signup, no email, and no limit on how many campaigns you run through it. It is built by Mage Loyalty, a loyalty, referrals and store credit app for Shopify.
Mage is a loyalty, referral and store credit app built for Shopify. Reward repeat purchases, run VIP tiers, and give customers a reason to come back, without writing a line of code.
