What Is VCPM?
VCPM (viewable cost per mille), also written viewable CPM, is the cost per thousand impressions that actually met a viewability standard — typically the IAB/MRC guideline of at least 50% of an ad's pixels in view for a minimum duration. It only counts impressions a person had a real chance to see.
Standard CPM is priced against every impression served, whether or not it ever rendered on-screen long enough to be seen. VCPM narrows the denominator to viewable impressions only, which is why a campaign's VCPM is almost always higher than its plain CPM — the same total cost is being divided by a smaller, stricter impression count.
VCPM Formula
Divide total cost by total viewable impressions, then multiply by 1,000.
VCPM = (Total Cost ÷ Viewable Impressions) × 1,000
Worked Example
A campaign spends $500 and serves 100,000 impressions, of which 80,000 are viewable.
VCPM = ($500 ÷ 80,000) × 1,000 = $6.25
Rearranged, the formula solves for cost or viewable impressions instead, which is what the other two modes above do:
Total Cost = (VCPM × Viewable Impressions) ÷ 1,000
Viewable Impressions = (Total Cost ÷ VCPM) × 1,000
Need the viewability rate itself first? Use the viewability rate calculator to find what share of served impressions were viewable, or compare against plain CPM and eCPM for the same campaign.
What Affects VCPM?
- Viewability rate — a lower share of viewable impressions pushes VCPM higher for the same total cost, since fewer impressions are counted in the denominator.
- Ad placement — above-the-fold and in-content placements typically achieve higher viewability than units low on a long page.
- Page layout and load speed — slow-loading pages and layout shifts reduce the time an ad is actually in view before a user scrolls past.
- Device and format — viewability standards and typical rates differ between desktop display, mobile, and video placements.
VCPM Calculator FAQ
How is VCPM calculated?
VCPM is calculated by dividing total ad spend by total viewable impressions, then multiplying by 1,000: VCPM = (Total Cost ÷ Viewable Impressions) × 1,000. Enter your cost and viewable impressions above to calculate it instantly.
What does VCPM mean?
VCPM stands for viewable cost per mille (or viewable CPM) — the cost per thousand impressions that actually met a viewability standard, such as the IAB/MRC guideline of at least 50% of an ad's pixels in view for 1 second (or 2 seconds for video).
What's the difference between VCPM and CPM?
CPM is priced against every impression served, whether or not anyone could actually see the ad. VCPM narrows the denominator to only impressions that met a viewability threshold, so it's typically a higher number than CPM for the same campaign — you're paying the same total cost for fewer "counted" impressions.
How do you convert CPM to VCPM?
Divide CPM by the viewability rate (as a decimal): VCPM = CPM ÷ Viewability Rate. A $5 CPM campaign with 70% viewability has a VCPM of $5 ÷ 0.70 = $7.14. Use the viewability rate calculator to find that rate from your own impression data.