What is CPA (Cost per Acquisition)?
Cost per Acquisition (CPA) is the average amount you spend on advertising to generate one conversion, whether that is a purchase, a lead, a signup, or any other defined action.
How It Works
CPA is calculated by dividing total ad spend by the number of conversions. If you spent $5,000 and generated 100 purchases, your CPA is $50. Some marketers use "Cost per Action" interchangeably, though CPA most often refers to a meaningful business outcome rather than a micro-conversion like a page view.
CPA is a more actionable metric than ROAS for many businesses because it directly ties to unit economics. If your average order value is $120 and your CPA is $40, you know exactly how much margin you keep per acquisition. This makes CPA the preferred metric for businesses with consistent order values or subscription models.
Different platforms may use different names for essentially the same metric. Google Ads calls it "Cost/conv." in its interface, Meta calls it "Cost per result," and LinkedIn uses "Cost per lead" for lead gen campaigns. The calculation is the same — spend divided by conversions — but the conversion event may differ by platform.
Why It Matters for Advertisers
CPA determines whether your advertising is profitable at the unit level. If your target CPA is $30 but your actual CPA is $45, you are losing money on every acquisition — even if your campaigns look healthy on vanity metrics like impressions and clicks.
CPA also helps you compare efficiency across platforms and campaigns. A LinkedIn campaign with $120 CPA might seem expensive compared to a Meta campaign at $25 CPA, but if LinkedIn leads convert to paying customers at 4x the rate, the effective CPA might actually be lower.
How Ad Superpowers Helps
Ad Superpowers gives you instant CPA visibility across all connected platforms. Ask "What is my CPA by campaign on Meta this month?" or "Compare CPA across platforms for the last 30 days." Our tools pull live data so you always see current numbers, not last week's export.
The cross-platform attribution reconciler skill also helps you understand true CPA by accounting for multi-touch attribution and deduplicating conversions that get counted by multiple platforms.
Related Terms
Return on Ad Spend (ROAS)
Return on Ad Spend (ROAS) is a marketing metric that measures the revenue earned for every unit of currency spent on advertising. A ROAS of 4x means you earn four dollars for every dollar spent.
Click-Through Rate (CTR)
Click-Through Rate (CTR) is the percentage of impressions that result in a click. It is calculated by dividing the number of clicks by the number of impressions and multiplying by 100.
Attribution Window
An attribution window (also called a lookback window or conversion window) is the time period after a user interacts with an ad during which a subsequent conversion can be attributed to that ad.
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