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CPA calculator (cost per acquisition)
Cost per acquisition is your ad cost divided by the conversions it produced: cost ÷ conversions. $3,000 of spend for 60 sales is a CPA of $50. Fill in any two values below and the calculator gives you the third.
By Alain Abulafya, founder of PPCleaner · Updated
PPCleaner
Every irrelevant click raises your CPA. PPCleaner reads your Google Ads search terms every night and blocks the ones that were never going to convert.
Start 7 days freeHow to calculate CPA
A conversion is whatever you count as a result: a sale, a lead, a booking, a sign-up. Make sure the cost and the conversions cover the same period and the same campaigns, or the CPA means nothing.
Your maximum CPA
The highest CPA you can afford is the margin a conversion brings in. If a sale leaves $80 of margin after the cost of goods, a CPA above $80 loses money on every sale. For customers who come back, use the margin over the whole relationship: the LTV and CAC calculator does it.
In Google Ads, that figure is what you would set as a target CPA in a Target CPA bidding strategy, minus the margin you want to keep.
How wasted clicks inflate CPA
Every click from a search that was never going to convert adds to the cost and nothing to the conversions. If 20% of your spend goes to those searches, your CPA is 25% higher than it needs to be: the same conversions for a fifth less cost would give 0.8 × CPA. Finding them means reading the search terms report; PPCleaner does it every night.
Frequently asked questions
Is CPA the same as CAC?
Not quite. CPA counts every conversion you track, which may be a lead or a free sign-up. CAC (customer acquisition cost) counts only new paying customers, and often includes more than ad spend.
What is a good CPA?
Any CPA comfortably below the margin a conversion brings in. Compare it with your own maximum CPA rather than with another business.
Why is my CPA higher in Google Ads than in my CRM?
The two count different things: Google Ads counts conversions by click date and within its attribution window, your CRM by sale date and from every source. Pick one source for decisions and stick to it.
Is my data stored?
No. The calculation runs in your browser.