eCPM

eCPM (effective cost per mille) is the actual revenue a publisher earns per 1,000 ad impressions delivered, regardless of the pricing model used (CPM, CPC, flat fee). It is calculated as: (Total Revenue ÷ Total Impressions) × 1,000. eCPM is the primary metric publishers use to compare the performance of different demand sources, campaigns, and ad placements. A higher eCPM means more revenue per impression. In newsletter advertising, eCPM typically ranges from $2–$4 for general-interest audiences and $8–$25+ for B2B, finance, or high-intent verticals. Open-time ad serving tends to produce higher eCPM than send-time serving because impressions are only counted for genuine opens, making each impression more valuable to advertisers.