CPM Calculator
Cost per thousand impressions, spend and reach.
Reviewed by James Whitfield · Updated 24 October 2026 · How we check our maths
Your values
ⓘ Live results
- CPM
- $5.95
- CPC (cost per click)
- $0.78
- CTR
- 0.762%
- Cost per conversion
- $19.53
- Conversion rate
- 4%
Quick answer
CPM (cost per mille) is what you pay for 1,000 ad impressions: total ad spend divided by impressions, multiplied by 1,000. A campaign that spends $2,500 for 420,000 impressions has a CPM of $5.95. CPC is spend divided by clicks, and CTR is clicks divided by impressions.
What the CPM calculator does
Enter what a campaign cost and what it delivered — impressions, clicks and conversions — and this calculator returns the five numbers media buyers compare most: CPM, cost per click (CPC), click-through rate (CTR), cost per conversion and the click-to-conversion rate. It works for any channel that reports impressions, including Meta, Google Ads, LinkedIn, TikTok, programmatic display and podcast or newsletter sponsorships.
CPM tells you the price of reach; it says nothing about whether that reach did anything. A cheap CPM with a tiny CTR can cost more per sale than an expensive CPM with an engaged audience, which is why the cost per conversion line matters most for direct-response campaigns. Feed that figure into a ROAS calculator to see whether the sales cover the spend.
Use numbers from the same date range and the same attribution setting in your ad platform. Mixing a 7-day-click conversion count with a 1-day-view impression report gives figures that look precise but do not belong together.
The formula
CPM = spend ÷ impressions × 1,000 CPC = spend ÷ clicks CTR = clicks ÷ impressions × 100 Cost per conversion = spend ÷ conversions Conversion rate = conversions ÷ clicks × 100
| Symbol | Meaning | Unit |
|---|---|---|
| spend | Total amount paid for the ads in the period | $ |
| impressions | Number of times the ad was served (or counted as viewable, depending on the platform) | count |
| clicks | Clicks or link clicks reported for the same period | count |
| conversions | Purchases, leads or sign-ups attributed to the ads | count |
These are the standard media-buying ratios used across the advertising industry and defined in marketing-metrics textbooks. "Mille" is Latin for thousand, so CPM is always quoted per 1,000 impressions. Note that the conversion rate here is per click, not per site visitor.
The same inputs cover the related CPC, CTR and CPV calculations this page replaces. For cost per view (CPV) on video ads, enter video views in the Clicks field: the CPC line then reads as cost per view.
Worked examples
Social awareness campaign
A local gym spends $1,200 on a social campaign that serves 150,000 impressions, gets 1,350 clicks and 27 trial sign-ups.
Inputs
- Ad spend1200 $
- Impressions150000
- Clicks1350
- Conversions27
Result
- CPM$8
- CPC (cost per click)$0.89
- CTR0.9%
- Cost per conversion$44.44
- Conversion rate2%
An $8 CPM and 0.9% CTR are reasonable for social, but $44.44 per sign-up only works if enough trials become paying members. The landing page, not the ad, is the next thing to test.
Cheap display retargeting
A display retargeting line spends $800 for 400,000 impressions, 480 clicks and 12 orders.
Inputs
- Ad spend800 $
- Impressions400000
- Clicks480
- Conversions12
Result
- CPM$2
- CPC (cost per click)$1.67
- CTR0.12%
- Cost per conversion$66.67
- Conversion rate2.5%
A $2 CPM looks like a bargain, but the 0.12% CTR means each click costs $1.67 and each order $66.67. Low CPMs often mean low-quality or low-visibility placements.
B2B LinkedIn campaign
A software company spends $5,000 on LinkedIn for 120,000 impressions, 600 clicks and 30 demo requests.
Inputs
- Ad spend5000 $
- Impressions120000
- Clicks600
- Conversions30
Result
- CPM$41.67
- CPC (cost per click)$8.33
- CTR0.5%
- Cost per conversion$166.67
- Conversion rate5%
A CPM above $40 is normal for narrowly targeted professional audiences. At $166.67 per demo the campaign is judged on pipeline value, not on reach.
CPM vs CPC vs CPA: which number to optimize
Each metric answers a different question, so the right one depends on the campaign goal.
| Goal | Metric to watch | Why |
|---|---|---|
| Brand awareness, reach | CPM (and frequency) | You are buying exposure; clicks are a bonus |
| Traffic to content | CPC and CTR | You pay for the visit, and CTR shows creative relevance |
| Sales or leads | Cost per conversion (CPA) | Ties spend to the outcome that earns money |
| Video views | CPV and view rate | Shows the cost of attention, not just a served ad |
| Profit | ROAS or ROI | Accounts for order value and margin, not just volume |
Why CPMs rise and fall
Most ad platforms run auctions, so CPM is set by competition for the audience you choose, not by a fixed price list.
- Audience size and value: narrow, high-income or B2B audiences cost more to reach than broad consumer audiences.
- Season: CPMs usually climb in the fourth quarter as retailers compete for holiday shoppers, then drop in January.
- Placement: in-feed and premium video inventory costs more than banner or audience-network placements.
- Ad quality: platforms reward ads people engage with, so a relevant creative can lower the price you pay for the same audience.
Because of this, compare CPMs against your own past campaigns on the same platform rather than against published averages.
Working backward from a target cost per sale
You can turn the formulas around to set a budget ceiling. Maximum CPC = target cost per conversion × conversion rate. If you can afford $40 per sale and 2.5% of clicks buy, you can pay up to $1.00 per click. Maximum CPM = maximum CPC × CTR × 10, so at a 0.8% CTR that is $8.00 per 1,000 impressions.
The same logic shows which lever matters: doubling CTR halves your effective CPC at the same CPM, and doubling the on-site conversion rate halves your cost per sale. Use an A/B test significance calculator before declaring a new ad or page the winner.
How to use the CPM Calculator
- 1Pick one campaign or ad set and one date range in your ad platform's reporting.
- 2Enter total spend, then impressions, clicks (or link clicks) and conversions from the same report.
- 3For video, put views in the Clicks field to read the CPC line as cost per view.
- 4Compare cost per conversion with what a customer is worth before judging the CPM.
Frequently asked questions
What does CPM stand for?
Cost per mille, from the Latin for thousand. It is the price of 1,000 ad impressions.
How do you calculate CPM from a budget?
Divide the budget by the impressions you expect and multiply by 1,000. To go the other way, impressions = budget ÷ CPM × 1,000, so $1,000 at a $5 CPM buys 200,000 impressions.
What is the difference between CPM and eCPM?
CPM is what an advertiser pays per 1,000 impressions. eCPM (effective CPM) is the same ratio from the publisher's side: revenue earned divided by impressions × 1,000, whatever pricing model the ads were sold on.
How do I calculate CPC and CTR?
CPC is spend divided by clicks, and CTR is clicks divided by impressions × 100. A $500 campaign with 100,000 impressions and 1,000 clicks has a $0.50 CPC and a 1% CTR.
How do I calculate cost per view (CPV)?
Divide video spend by the number of views the platform counts. $600 for 20,000 views is a $0.03 CPV. Platforms define a view differently, so compare CPV within one platform.
Is a lower CPM always better?
No. A low CPM with poor engagement can produce a higher cost per sale than a premium placement. Judge campaigns on cost per conversion and return on ad spend.
References
- Marketing Metrics: The Manager's Guide to Measuring Marketing Performance — Farris, Bendle, Pfeifer & Reibstein (Pearson)
- Glossary of Interactive Advertising Terms — Interactive Advertising Bureau (IAB)
About this calculator
- Built and reviewed by James Whitfield · How we build and test calculators
- Last reviewed: October 24, 2026
- Report an error