Media Math Calculator (CPM, CPC, CPA)
Enter spend, impressions, clicks, and conversions to get all the core paid-media numbers at once: CPM, CPC, CTR, CPA, and conversion rate.
Your numbers
Results update live
CPM
$4.00
Cost per 1,000 impressions
CPC
$0.27
Cost per click
CTR
1.50%
Click-through rate
CPA
$6.67
Cost per acquisition
Conversion rate
4.00%
Conversions per click
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HubSpot Marketing Analytics
Track CPM, CPC, and CPA across every channel in one dashboard instead of exporting reports by hand.
How this is calculated
- CPM = spend / impressions x 1,000.
- CPC = spend / clicks.
- CTR = clicks / impressions x 100.
- CPA = spend / conversions.
- Conversion rate = conversions / clicks x 100.
These are the standard definitions used across ad platforms. For typical ranges by industry, reported figures like the WordStream Google Ads benchmarks are a reasonable reference point.
Frequently asked questions
What is the difference between CPM, CPC, and CPA?
CPM is the cost per thousand impressions, CPC is the cost per click, and CPA is the cost per acquisition or conversion. They measure cost at different stages of the funnel, so a campaign can look cheap on CPM and expensive on CPA.
How is CTR calculated?
Click-through rate is clicks divided by impressions, as a percentage. It tells you how compelling the ad is at getting the click, separate from what happens after.
Which metric should I optimize for?
Usually CPA, because it ties spend to an actual outcome. CPM and CPC are useful for diagnosing where a campaign leaks, but CPA is the one that maps to money.