SEA: definition
Paid advertising on search engines (like Google Ads): you buy visibility on specific queries, as opposed to free SEO.
By Mathéo Ballasse · June 12, 2026
Definition
SEA (Search Engine Advertising) means paying to appear at the top of search results for specific keywords. Unlike SEO, the effect is immediate but stops dead the moment you cut the budget. It's a powerful channel when purchase intent is clear, provided you control cost per click and conversion rate.
How to calculate it
Cost per acquisition = campaign spend / number of conversions
Why it matters
SEA captures people at the exact moment they're searching for a solution: intent is high, so conversion can be too. But since you pay for every click, poor targeting or a weak landing page drives up CAC fast: it's a channel that punishes imprecision.
When to use it
You use it when there are high-intent queries tied to your product and your unit economics can support it. Concretely, you start small on a few highly qualified keywords, measure cost per acquisition, and only scale the budget on what's profitable.
Example
A billing SaaS that bids on the keyword "invoicing software for freelancers" to appear above the organic results.
Common mistakes
- Bidding on keywords that are too broad.
- Sending paid traffic to a weak landing page.
- Scaling the budget before proving profitability.
Don't confuse it with
- seo: SEO is free and cumulative but slow; SEA is paid and immediate but stops the moment you cut the budget.
Related terms
Articles that use this term
Frequently asked questions
- SEA or SEO to get started?
- SEA to quickly test demand and generate immediate sales; SEO in parallel to build a free, durable flow that will take over later.