CPA
Cost Per Acquisition
In one line
Cost per acquisition (CPA) is the average marketing spend required to generate one conversion — used to judge whether a channel or campaign is paying its way.
Going deeper
CPA is your spend divided by the number of conversions. Because it is comparable across channels and campaigns, it usually drives the budget reallocation conversation each month.
Read CPA next to LTV. If lifetime value is not comfortably greater than acquisition cost, scaling spend just scales losses — the 3:1 rule of thumb for healthy unit economics is really LTV-to-CAC, with CPA (cost per single conversion) sitting underneath as one input into the broader CAC figure.
Driving CPA down is not automatically a win. Push too hard and the addressable audience shrinks until volume collapses. The real job is balancing efficiency with the volume the business actually needs.
Related terms
CAC
Customer acquisition cost (CAC) is the total marketing and sales spend required to win one new paying customer.
MarketingLTV
Lifetime value (LTV) is the estimated total revenue — or profit — a single customer is expected to generate over the entire relationship with your business.
MarketingROAS
Return on ad spend (ROAS) is revenue divided by ad spend — the headline efficiency metric for performance campaigns where revenue can be tracked back to the channel.
MarketingCVR
Conversion rate (CVR) is the percentage of visitors or clicks that complete a defined goal — purchase, signup, lead form — and is the headline efficiency metric for most digital campaigns.
MarketingPaid Media
Paid media is any channel where you pay to be seen — search ads, display, social ads, video and OTT all fall under this umbrella.
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