Two views of the same spend
Average cost per click equals spend divided by clicks. Effective cost per thousand impressions equals spend divided by impressions, then multiplied by 1,000. With $1,200 spent, 600 clicks, and 100,000 impressions, CPC is $2 and CPM is $12. These describe the same campaign from different denominators.
Use compatible figures
Keep spend, clicks, and impressions in the same campaign and date range. A platform's reported average CPC or CPM may differ if it counts different interactions, fees, or impression types. Neither metric says whether the clicks were qualified or whether the campaign produced a useful outcome.
Google Ads: average CPC · Google Ads: CPM and campaign columns