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Marketing glossary
What is click-through rate (CTR)?
Click-through rate shows how often exposure turns into a click. It is a useful diagnostic measure for creative and message relevance, provided you resist the tempting fiction that every click is equally valuable.
What click-through rate means
The standard formula is:
CTR = clicks ÷ impressions × 100
If a search advert appears 10,000 times and receives 350 clicks, its CTR is 3.5%. For email, the denominator may be delivered emails rather than impressions. Some email systems also report click-to-open rate, which divides clicks by opens. Check the platform’s definition before comparing figures.
CTR depends heavily on context. A branded search advert, an unsolicited display advert and a customer email serve different audiences at different moments. Their percentages are not sensible league-table competitors.
A practical SME example
A commercial cleaning company runs two search adverts for the same service. Advert A receives 120 clicks from 4,000 impressions, giving it a 3% CTR. Advert B receives 90 clicks from 2,000 impressions, giving it a 4.5% CTR.
Advert B attracts a higher proportion of searchers, perhaps because its promise fits their search intent more closely. Yet the company should still check enquiry quality and cost. If Advert A produces 12 suitable leads while Advert B produces three job applications and two irrelevant calls, Advert A contributes more to the objective.
Why CTR matters
CTR can help you:
- compare messages shown in the same channel to similar audiences;
- identify weak headlines, offers, imagery or calls to action;
- detect a mismatch between a keyword, advert and landing page;
- monitor whether an audience has become tired of repeated creative;
- diagnose a journey before analysing conversion and revenue.
It works best as one step in a measurement chain: impressions show opportunity, CTR shows immediate response, conversion rate shows completed action and revenue measures commercial value.
Common mistakes
One mistake is pursuing curiosity clicks. A dramatic headline can lift CTR while setting an expectation the landing page cannot fulfil. The result is more traffic, a worse conversion rate and a larger bill.
Another is comparing platform reports without checking what counted as an impression or click. Social platforms may include several interaction types, while analytics software records website sessions under different rules. Privacy controls and accidental clicks add further noise.
Small samples also mislead. Ten clicks from 100 impressions creates a 10% CTR, but one additional click moves the rate considerably. Make decisions only after the campaign has generated enough relevant exposure to show a useful pattern, and segment results by audience, device, placement and search term where appropriate.
Related guides
Related terms
What is a good click-through rate?
There is no universal good CTR. It varies by channel, format, audience, position, industry and objective. Compare like with like, use your own historical performance as a baseline and judge clicks by the qualified outcomes they create.
Can CTR be higher than 100%?
Some reporting systems can show more clicks than unique impressions because one person clicks multiple times or because the metrics use different counting rules. Standard advert CTR is usually interpreted as clicks divided by impressions, so investigate the platform’s methodology if it exceeds 100%.
Who wrote this
Steve Ward.
Steve founded Epitomise in 2017 after UK, international and global marketing leadership roles, most recently as Global CMO of the Vitec Group’s Videocom Division. He works with SME and technology businesses on strategy, positioning and the execution that follows — more about Steve.
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