eCPM and EPC Explained for Publishers

What are eCPM and EPC?

EPC (earnings per click) is what you earn on average each time a user clicks an offer: earnings divided by clicks. eCPM (effective cost per mille) is what you earn per 1,000 impressions: earnings divided by impressions, times 1,000. For an offerwall, EPC tells you how well offers convert once users pick one, and eCPM tells you what each opening of the wall is worth.

Both are publisher metrics, and they answer different questions. This guide shows how to calculate each one on an offerwall, how they fit together, and which changes on your side move them. If you want the difference between eCPM and page RPM on a website, read eCPM vs RPM.

EPC: earnings per click

EPC = earnings ÷ clicks. On an offerwall, a click is when a user opens an offer. If 400 offer clicks earned you $30, your EPC is $0.075.

EPC is the product of two smaller numbers: EPC = conversion rate × average payout per conversion. A 5% conversion rate at a $1.50 average payout gives an EPC of $0.075. That split is useful, because it tells you whether a low EPC comes from users not finishing offers or from offers that pay little.

Watch out when you compare with affiliate marketing. Some affiliate networks report EPC per 100 clicks, not per click. CJ, for example, labels its 7-day and 3-month EPC as “Average Earnings Per One Hundred Clicks” in its API documentation, and the FlexOffers glossary defines EPC as “the average earnings per 100 clicks”. An EPC of $7.50 there would be $0.075 per click here.

eCPM: earnings per 1,000 impressions

eCPM = earnings ÷ impressions × 1,000. It puts the offerwall on the same scale as banner or video ads: the Google AdMob reports glossary defines eCPM the same way, as the estimated earnings for every 1,000 impressions an ad receives. If the wall was opened 10,000 times and earned $60, its eCPM is $6.

On an offerwall, the “impression” is one opening of the wall, and eCPM links back to EPC: eCPM = EPC × clicks per wall opening × 1,000. If 20% of openings lead to an offer click and your EPC is $0.075, your eCPM is $15. So eCPM can rise even when EPC stays flat, simply because more openings turn into clicks.

Offerwall users often complete several offers over days, though, so many publishers also track earnings per 1,000 active users. It shows the value of your audience better than a single visit does.

eCPM vs EPC vs other offerwall metrics

Use EPC to judge offers and countries, eCPM to compare placements, and earnings per 1,000 active users to compare the offerwall with other formats such as display ads or rewarded video.

How to calculate eCPM and EPC: a worked example

Now check the links between them. The average payout is $180 ÷ 120 = $1.50, and 7.5% × $1.50 = $0.1125, the same EPC. One in five openings led to a click, and $0.1125 × 0.2 × 1,000 = $22.50, the same eCPM. Once you see these pieces, you know exactly which one to work on.

Other numbers worth watching

• Conversion rate: completed offers divided by clicks. Low rates can mean your users see offers that do not fit their country or device.
• ARPU: average revenue per user, total earnings divided by active users in the period.
• Monetized users: the share of active users with at least one confirmed conversion.
• Chargeback rate: reversed conversions divided by all conversions. A rising rate is an early warning about traffic quality.

How to raise your share of monetized users

Getting one more user in ten to complete a first offer often does more for revenue than a new traffic source. Start here:

1. Explain the offerwall on your site in one sentence, so users know what they can earn and how.
2. Show it at the right moment, for example when a user runs out of your currency or wants a premium item.
3. Credit rewards quickly after each postback, and show a clear history so users trust the process.
4. Keep your reward rate competitive, since users compare what the same effort earns elsewhere.

Reading your Moonetix dashboard

Your Moonetix Dashboard shows four cards for the period you pick, the last 30 days by default, each compared with the period before: clicks, earnings, conversions, and conversion rate. Divide earnings by clicks and you have your EPC for that period. The Top offers panel shows your earnings and EPC for each offer, for today, 7 days, or 30 days. Each app page adds its active users, monetized users, clicks, and earnings for the last 30 days, so you can compare apps side by side.

For EPC by day, offer, country, sub ID, app, or device, open Reports, Performance, or use the Reporting API. Moonetix counts offer clicks, not each opening of the wall, so to calculate eCPM per wall opening, count openings on your own side, for example each time your page loads the wall. How to read your dashboard and reports explains every figure.

What raises your eCPM and EPC

Placement comes first: a visible link in your menu or reward screen beats a hidden page. Offerwall placement covers where to put it. Your exchange rate comes next, because it decides how rewarding an offer looks to your users; How to set your virtual currency exchange rate walks through the math. Geography matters too, since advertisers bid per country and the same effort can pay differently around the world.

Then protect what you earn. Reversed conversions cost you twice, once in payout and again in advertiser trust, so keep your traffic clean. And credit fast: users who receive rewards quickly come back for more.

It helps to know which lever moves which number. Offer fit, country mix, and your reward rate mostly move EPC. Placement and the wording around your wall link mostly move clicks per opening, and with it eCPM. Everything that brings users back moves earnings per 1,000 active users.

Common eCPM and EPC mistakes

• Judging a change after two days. Many offers confirm later than the click, so recent days always look weaker. Compare full 7-day or 30-day periods.
• Comparing your EPC with a figure quoted per 100 clicks, or your eCPM per wall opening with someone else’s page RPM. Check the denominator first.
• Chasing EPC alone, for example by pointing users only at the highest-paying offers. EPC may rise while total earnings fall, because fewer users find something they actually want to do.
• Counting gross earnings. Reversed conversions come off your earnings, so use confirmed numbers net of reversals.
• Mixing all countries into one number. A shift in country mix can move EPC more than any change you made, so check results by country before drawing conclusions.

Where to go next

To turn these metrics into a revenue estimate, read How much can you earn with an offerwall?

Frequently asked questions