What is click through rate (CTR)?
Divide clicks by impressions and multiply by a hundred. If an ad was shown ten thousand times and two hundred people clicked, the CTR is two percent. The same arithmetic applies to a search result, an email link, a thumbnail, a call to action on a landing page: anywhere something is shown and can be clicked. It measures one thing precisely, whether the thing shown was compelling enough to act on, and it is the first number anyone looks at when a campaign goes live.
It is a rate, so it strips out scale. A small campaign with a high CTR and a huge campaign with a low one can be compared on the same footing, which is why it became the universal currency of digital advertising.
Why it matters
Why click through rate matters
It is the fastest read on creative. Two ads with the same audience and the same placement, different CTRs: the creative is the difference, and you know within a day. In paid search and paid social, a higher CTR also lowers the price, because platforms reward ads that people respond to with better quality scores and cheaper clicks (CPC). In email it tells you whether the message earned the open it got.
It is also where campaigns go wrong, because a click is not a customer. An ad can earn a high CTR by promising something the landing page does not deliver, and the clicks cost money while the conversions never arrive.
In practice
How click through rate works in practice
- 01
Benchmark it in context. CTR varies enormously by channel, format, industry and placement, and the only meaningful comparison is against your own history and against variants running side by side. Set up every campaign to test: two or three creatives, two or three headlines, and let the CTR sort them before the budget is committed to one. That is A/B testing at its simplest.
- 02
Then read it with the next number. Pair CTR with conversion rate and cost per result so the creative that wins clicks is also the one that wins outcomes. A creative with a modest CTR and a strong conversion rate often beats a click magnet that bounces. The platforms report all three; the discipline is looking at them together.
At RIOT
Click through rate at RIOT
On the Meta ad engine we ran for Homebase from February to April 2025, click through rate was the first filter in a weekly loop: new creative went in, the versions people clicked earned more budget, the versions they did not were replaced, and the next round was built from what the clicks had taught us. It is the fastest feedback a creative team gets, and the loop only works if someone is reading it every week.
Watch out
What people get wrong about click through rate
Treating it as the goal. A campaign optimized for CTR alone attracts the curious rather than the convinced, and the cost shows up two steps later as poor conversion. The other mistake is comparing across channels: a two percent CTR is excellent for display advertising and poor for branded search, and a report that averages them has said nothing.
Ignoring it in organic search, where the CTR of a result is the clearest signal that a title and description are doing their job, and where it can be improved without spending anything.
