eCPM Calculator
(Effective Cost Per Mille Tool)
This free eCPM calculator helps publishers and app developers instantly calculate effective cost per 1,000 impressions, forecast ad revenue, and check fill rate.
Step 1 — Calculation Goal
What would you like to calculate?
Step 2 — Core Metrics
Total revenue earned from ads in the period
Total number of ad impressions delivered
eCPM Result
💡 Formula Guide
Related Calculators
What Is eCPM? (Effective CPM — Explained)
eCPM, or effective Cost Per Mille, measures how much ad revenue a publisher earns per 1,000 impressions — calculated after the fact from actual revenue, regardless of which pricing model generated it. "Mille" is Latin for thousand, the same root used in CPM (Cost Per Mille), the advertiser-facing buying price for impressions.
The key distinction: CPM is what an advertiser pays, agreed in advance as a fixed rate per 1,000 impressions. eCPM is what a publisher earns, calculated from real revenue after the fact — which matters because publishers often run a mix of CPC (cost-per-click), CPA (cost-per-action), and CPM campaigns simultaneously through ad networks or mediation platforms. eCPM normalizes all of that into one comparable per-1,000-impression number, so a publisher can compare a CPC-based ad network against a fixed-CPM deal on equal footing.
The eCPM Formula
eCPM Calculation Example
Suppose your app or site earned $250 in ad revenue from 100,000 impressions.
This means you earned $2.50 for every 1,000 ad impressions shown — a useful comparison point across ad networks, formats, and time periods, even when the underlying pricing models differ.
eCPM vs CPM — Buyer Price vs Publisher Earnings
| Feature | CPM | eCPM |
|---|---|---|
| Who Uses It | Advertisers (buy-side) | Publishers (sell-side) |
| When Set | Agreed in advance | Calculated after impressions delivered |
| Underlying Pricing | Fixed per-1,000-impression rate | Can derive from CPC, CPA, or CPM revenue |
| Purpose | Budgeting ad spend | Comparing revenue across ad sources |
A publisher running a CPC-based ad network can still calculate an eCPM to compare it against a fixed-CPM deal from another network — even though the advertiser on the CPC network never agreed to a per-1,000-impression rate at all. This is why eCPM, not CPM, is the standard revenue-comparison metric on the publisher side.
Fill Rate — The Metric to Track Alongside eCPM
Fill rate measures what share of your ad requests were actually filled with a served impression — and it matters because eCPM alone doesn't tell you your total revenue.
A high eCPM with a low fill rate can still produce disappointing total revenue, because most of your available ad inventory went unsold. Conversely, a lower eCPM with a very high fill rate can outperform it in total dollars. Total Revenue is ultimately a function of both: Revenue = (Ad Requests × Fill Rate × eCPM) ÷ 1,000. Publishers and app developers generally track fill rate and eCPM together, not eCPM in isolation.
How to Use This Free eCPM Calculator
Step 1 — Choose Your Calculation Goal
- eCPM: You know your revenue and impressions — calculate your effective CPM
- Expected Revenue: You have an eCPM target and impression forecast — calculate expected earnings
- Required Impressions: You have a revenue goal and eCPM — calculate impressions needed
Step 2 — Enter Core Metrics
- Total Ad Revenue: Total earnings from ads in the period (e.g., $250)
- Total Impressions Served: Total ad impressions delivered (e.g., 100,000)
Step 3 — Optional: Fill Rate Settings
Add Total Ad Requests to see your fill rate alongside your eCPM result.
💡 Pro Tip: Compare eCPM across ad networks over the same time window and geography — eCPM shifts significantly by season, ad format, and audience location, so a single snapshot number isn't enough to judge network performance.
Frequently Asked Questions About eCPM
What does eCPM stand for?
eCPM stands for effective Cost Per Mille — the effective revenue a publisher earns per 1,000 ad impressions, calculated from actual revenue after impressions are delivered. Formula: eCPM = (Total Ad Revenue ÷ Total Impressions) × 1,000.
Is eCPM the same as CPM?
No. CPM is the price an advertiser agrees to pay per 1,000 impressions, set in advance. eCPM is calculated after the fact from real revenue and is used by publishers to compare earnings across ad networks that may use CPC, CPA, or CPM pricing internally.
How do I increase my eCPM?
Common levers include using higher-value ad formats (rewarded video and interstitials typically outearn banners), improving ad placement and viewability, enabling header bidding or mediation to create competition between demand sources, and targeting higher-value geographies and audience segments.
What's a typical eCPM range?
eCPM varies enormously by ad format, vertical, and geography — banner ads often fall in the $0.10–$2 range while rewarded video in mobile games can reach $5–$20+. There's no single universal benchmark; compare your own eCPM over time and against your specific format and traffic source.
How does fill rate affect total ad revenue?
Total revenue depends on both eCPM and fill rate: Revenue = (Ad Requests × Fill Rate × eCPM) ÷ 1,000. A high eCPM with a low fill rate can still underperform a lower eCPM with a much higher fill rate, since fill rate determines how much of your inventory actually generates revenue.
Can I use this calculator for AdMob, Google Ad Manager, or Meta Audience Network?
Yes. eCPM is the standard revenue metric reported across mobile mediation platforms (AdMob, Unity Ads, Meta Audience Network) and website ad servers (Google Ad Manager). The formula is identical across platforms.
Last Updated: September 2026.