CPM Calculator: Work Out CPM, RPM and eCPM
Use this free CPM calculator to find your cost per 1,000 impressions, your page RPM or your eCPM. Fill in any two numbers and the calculator works out the third one. It is useful for advertisers who plan a budget and for publishers who want to understand their ad revenue.
Fill in any two fields and press Calculate. The tool works out the third one.
Formula: CPM = cost ÷ impressions × 1,000
Use the earnings and pageviews from your AdSense or ad network report. Fill in any two fields.
Formula: Page RPM = earnings ÷ pageviews × 1,000
eCPM shows what each 1,000 ad impressions really earned, no matter how the ads were sold (CPM, CPC or CPA). Fill in any two fields.
Formula: eCPM = earnings ÷ ad impressions × 1,000
How to use the CPM calculator
- Choose a tab: CPM for ad buying, Page RPM or eCPM for publisher earnings.
- Enter any two values, for example cost and impressions.
- Press Calculate. The missing value is filled in and highlighted.
- Change a number and press Calculate again to compare scenarios.
CPM, RPM and eCPM formulas
All three metrics use the same idea: a value per 1,000 units. However, the units are different, and that is where most confusion starts.
| Metric | Formula | Who uses it |
|---|---|---|
| CPM (cost per mille) | Cost ÷ impressions × 1,000 | Advertisers, to price campaigns |
| Page RPM | Earnings ÷ pageviews × 1,000 | Publishers, to measure a whole page |
| Impression RPM | Earnings ÷ ad impressions × 1,000 | Publishers in AdSense reports |
| eCPM (effective CPM) | Earnings ÷ ad impressions × 1,000 | Publishers and ad networks, to compare partners |
For example, a page with three ad slots can earn a $2 eCPM per ad but still reach a $6 page RPM. Therefore page RPM is the best number for comparing how much your content earns. We explain this in detail in RPM vs CPM vs eCPM.
Typical CPM ranges in 2026
Rates change by country, season, ad size and format. As a rough guide, display ads on content sites often earn between $0.50 and $5 eCPM, while video ads usually earn more. Prices are highest in the fourth quarter, when advertisers spend their holiday budgets, and lowest in January.
For real numbers, see our Google AdSense CPM rates and YouTube CPM rates 2026. Then estimate your monthly earnings with the ad revenue calculator.
How to increase your CPM and RPM
- Improve viewability. Ads that are actually seen get higher bids. Place units near the content people read.
- Use popular sizes. 300×250, 336×280, 728×90 and 300×600 have the most demand. Check our banner ad sizes guide.
- Add more demand. With header bidding many buyers compete for every impression, so the price goes up.
- Keep pages fast. Slow pages lose visitors before the ads load.
- Keep ads.txt clean. Buyers skip unauthorized sellers. Build a correct file with our ads.txt generator.
Frequently asked questions
How do you calculate CPM?
Divide the total cost by the number of impressions and multiply by 1,000. For example, $500 ÷ 250,000 impressions × 1,000 = a $2.00 CPM.
What is the difference between CPM and RPM?
CPM is the price for 1,000 ad impressions, and advertisers usually pay it. RPM is what a publisher earns per 1,000 pageviews or impressions. Because a page can show several ads, page RPM is often higher than the CPM of a single ad.
What is a good page RPM for a website?
It depends on the niche and the audience. Many content sites with mostly US traffic see a page RPM between $5 and $30. Finance and B2B sites can be higher, while entertainment and sites with mostly non-US traffic are often lower.
Is eCPM the same as CPM?
Not exactly. CPM is the agreed price per 1,000 impressions. eCPM (effective CPM) is calculated afterwards from what you really earned, so it also covers ads that were sold per click or per action.
Can I use this CPM calculator for Facebook or Google Ads?
Yes. The CPM formula is the same on every platform. Enter your total spend and impressions from the ads report to get your CPM.