Free Tool

eCPM & Fill Rate Calculator

Measure newsletter ad performance with two core publisher metrics: effective CPM (actual revenue per 1,000 impressions) and fill rate (percentage of ad requests fulfilled).

Performance inputs

Revenue$2.0k
Delivered impressions500.0k
Ad requests550.0k
Filled impressions485.0k

Effective CPM (eCPM)

$4.00

eCPM = (Revenue ÷ Delivered Impressions) × 1,000

Fill rate

88.2%

Fill rate = (Filled ÷ Ad Requests) × 100

At current eCPM, unfilled requests represent approximately $260.00 in potential revenue per period.

eCPM tells you how much you actually earned per 1,000 delivered impressions across all demand sources — direct-sold, programmatic, and house ads combined. It is the primary metric for comparing waterfall tiers and placement performance.

Fill rate measures inventory utilisation. Publishers on MailAdx typically achieve 90–97% fill rates once programmatic demand is configured. Every unfilled impression represents lost revenue — the calculator estimates that gap at your current eCPM.

Improve fill rate and eCPM

MailAdx's waterfall fills unsold inventory with programmatic demand and optimises floor prices.

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Setup in 30 minutes
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