How the cpc to cpa calculator works
Cost per acquisition (CPA) is what you pay in ads for each sale or sign-up. It follows directly from how much a click costs and how many clicks turn into customers.
Clicks = Budget ÷ CPC · Conversions = Clicks × Conversion rate
Max CPC = Target CPA × Conversion rate
Improving the landing page conversion rate lowers CPA just as effectively as cheaper clicks. Doubling conversion from 2% to 4% halves CPA. Use the max CPC figure to set bids: if a customer is worth $40 to you and 3% of clicks convert, you can pay up to $1.20 a click and break even.
Worked example
A $1,000 budget at $1.50 per click buys 667 clicks. At a 3% conversion rate that is 20 sales, a CPA of $50.00. At an $80 average order, revenue is $1,600. To bring CPA down to $40 at the same conversion rate, bids would need to average $1.20.
Frequently asked questions
How do I calculate CPA?
Divide total ad spend by conversions, or divide CPC by conversion rate.
What is a good conversion rate?
It varies by industry and traffic source; 2% to 5% is common for e-commerce search traffic.
What is the difference between CPC and CPA?
CPC is the cost of a click; CPA is the cost of a customer or lead.
How do I lower CPA?
Raise conversion rate, improve targeting and ad relevance to lower CPC, or cut poor-performing keywords.
Updated October 2026. Results are estimates for education, not financial or medical advice. All math runs in your browser; nothing you type is sent anywhere.