Retargeting is an advertising technique that shows your ad again to people who have already visited your website on other websites, in search results or in social media feeds. The embedded pixel recognises returning visitors and shows them exactly the products or services they have already looked at.
How does retargeting work technically?
The foundation is the pixel, a tiny piece of code you embed on your website. When a visitor loads your page, the pixel sets a cookie-based ID on the visitor's device and sends it to the advertising platform (Google, Meta or another provider), which later shows your ad to that visitor on other websites, in search results or in social media feeds. Which page visits count as relevant is decided by the conversion events you define, for example "viewed basket" or "sent enquiry".
| Component | Function |
|---|---|
| Pixel (tracking code) | Sets an ID on the visitor's device and sends the information to the advertising platform |
| Advertising platform (Google, Meta) | Stores the visitor information and shows the ad on the relevant platforms |
| Conversion events | Define which page visits count as "relevant" (e.g. basket, enquiry) |
Which consent rules apply?
In Germany this is the decisive question. Under section 25 of the German TDDDG (the telecommunications and digital services data protection act), cookies or similar techniques that store or read information on a device generally need the visitor's consent before the pixel is set. If personal data is processed, the GDPR applies on top. In practice that means:
- The cookie banner must offer a genuine choice, "Accept" and "Reject" must be equally prominent.
- The consent must be documented (who, when, for which purpose) and can be withdrawn at any time: the pixel must then be disabled.
- A mere "clicking on" or "scrolling" is not sufficient as consent.
How many ads per person are sensible?
Too few ads and the visitor forgets about your site. Too many and they get annoyed and click away. There is no universal number. As a starting point for a test, we suggest three to five ad impressions per person per week; then watch how the responses develop. In addition you should:
- Use different ads, when the same ad is shown again and again, it quickly feels repetitive.
- Limit the duration to 30 to 60 days, after that, the probability that the visitor is still relevant drops.
- Check your exclusion logic: people who have already bought or enquired should be removed from the retargeting pool.
When is retargeting worth it?
Retargeting is not a panacea. It pays off when:
- You have enough traffic with fewer than a few hundred visitors per month the data is too thin for reliable statements.
- Your target group is recognisable and you can find it again in the advertising platforms.
- Your product or service justifies repeated consideration, e-commerce, B2B services with a longer decision phase, courses, SaaS.
Retargeting is not worth it on a pure landing page with little traffic, when your target group is very local and already reachable via other channels, without a consent management, or for a "buy on first sight" product with no further decision process.
Checklist: preparing your retargeting
Before you start retargeting, a short self-test is worth it:
- The pixel is embedded on all relevant pages and the consent in the cookie banner is active and documented (who, when, for which purpose)
- Conversion events are defined (basket, enquiry, contact form)
- Frequency and duration are limited (starting point: 3 to 5 impressions per person and week, 30 to 60 days)
- The exclusion logic is set (people who have already bought or enquired are excluded)
- You have a measurement plan (enquiries, cost per enquiry)
Conclusion: retargeting is a tool, not a miracle
Retargeting is a useful tool to bring returning visitors back to your site and close the purchase or the enquiry. The decisive factor is consent: in Germany the pixel generally needs prior, properly documented consent.
Start with a limited test, 30 to 60 days, a clearly defined target group, clean measurement. Then you will know whether retargeting works for your business. For the bigger budget picture, see our article How much budget do you need for online marketing?, and for the next step What is conversion optimisation?.
And if you are not sure whether retargeting makes sense for your target group: talk to us: we will check together whether it fits your business. More about our approach: Digital marketing.
Sources
- Gesetze im Internet: Section 25 TDDDG (German)
- EUR-Lex: General Data Protection Regulation (EU) 2016/679
- Meta: Meta Pixel
- Google: About remarketing
