CPM, CPC, CTR, CPA and ROAS calculator
Paste in the five numbers every ad platform gives you and get every metric that matters, with a funnel that shows where the money leaks between the impression and the sale.
How it is calculated
CPM = Spend ÷ Impressions × 1,000 CTR = Clicks ÷ Impressions × 100 CPC = Spend ÷ Clicks Conversion rate = Conversions ÷ Clicks × 100 CPA = Spend ÷ Conversions ROAS = Revenue ÷ Spend AOV = Revenue ÷ Conversions
The metrics chain together: CPA equals CPC divided by conversion rate, and CPC equals CPM divided by 1,000 times CTR. That chain is the useful part. If CPA rises, it tells you whether the cause is a more expensive audience (CPM), weaker creative (CTR) or a weaker landing page or offer (conversion rate).
How to use the result
Compare the funnel week on week rather than reading any metric alone. A rising CPM with a steady CTR usually means auction pressure or seasonality; a falling CTR at steady CPM points to creative fatigue; a falling conversion rate with steady CTR points to the page, the price or stock.
Questions
How do you calculate CPM?
Divide ad spend by impressions and multiply by 1,000. ₹1,00,000 spent on 5,50,000 impressions is a CPM of about ₹182.
How do you calculate CTR?
Divide clicks by impressions and multiply by 100. 6,600 clicks from 5,50,000 impressions is a CTR of 1.2%.
What is the difference between CPA and CPC?
CPC is the cost of a click; CPA is the cost of a conversion such as a purchase. CPA equals CPC divided by conversion rate, so a ₹15 CPC at a 2% conversion rate is a ₹750 CPA.
What is a good CTR for Meta or Google ads?
It varies widely by format, placement and industry, so compare against your own history. A CTR that is improving while CPA also improves is good; a high CTR with a poor CPA usually means the ad attracts curiosity rather than buyers.
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