Business & pricing

eCPM: Definition, Formula and Example

eCPM expresses advertising cost or revenue per 1,000 impressions; the reporting viewpoint and impression denominator must be specified.

Scope: Advertising reporting concept; AdSense’s current RPM terminology is distinguished from historical eCPM naming.

Other names and related labels: Effective cost per thousand impressions; Ad impression RPM.

How it works

For a publisher, effective revenue per thousand ad impressions can summarize mixed advertising revenue. AdSense uses RPM terminology in its current reports; page RPM uses page views, while ad RPM uses ad impressions. A page can contain several ads, so these measures need not match.

Publisher ad eCPM = ad revenue / ad impressions × 1,000

Use revenue and impressions from the same period, currency and reporting scope. Advertiser cost-based eCPM uses spending instead of publisher receipts.

$120 earned from 40,000 ad impressions

Assume the revenue and impression counts use the same reporting basis.

  1. Revenue per impression: $120/40,000 = $0.003.
  2. Per thousand: $0.003 × 1,000 = $3.

The illustrated ad eCPM is $3; it is not revenue per visitor or per page view.

Hypothetical publisher revenue; no claim about future earnings, fill rate or a network payout.

This example uses publisher revenue and ad impressions. Page views are a different denominator.

An effective average is not a guaranteed CPM bid

Revenue can change with geography, device, demand, fill and reporting adjustments. Do not multiply page views by ad eCPM without accounting for the number of counted ad impressions. This site does not currently offer an advertising-report calculator.

Sources and checks

Calculation methodology and review status · All glossary terms