The goal of link building is to strengthen your own website with positive signals. However, not every link sends such a signal – some links can even have a harmful effect. It is therefore all the more important to know how to evaluate a domain you want a link from using a set of KPIs. Below, we present four criteria for evaluating a domain.
Visibility Index (Sistrix)
The Visibility Index is a metric from the tool "Sistrix" that has become particularly established in Germany. It describes how visible a domain is in search results. Since this metric is tracked historically, the development of a website can be traced over time – rises and falls of a domain are visible across the timeline.
The Visibility Index is calculated as follows: For each country, there is a keyword pool (1,000,000 keywords for Germany). Three components feed into the calculation:
- For how many of those keywords does the site rank?
- What is the search volume for those keywords?
- How well does the site rank for those keywords?
The more positively these three questions can be answered, the higher the Visibility Index of a website.
Notes for evaluating this KPI:
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This KPI is only one indicator. Even pages with a low Visibility Index can be highly relevant for your link building strategy. Websites operating in a niche market may never achieve a high visibility score – simply because there are not many keywords worth ranking for, and also because of the comparatively low search volume. Of course, such websites are still very important if you are trying to establish yourself in that market.
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Do not compare the Visibility Index across countries! Each country has its own database and thus a different calculation basis. In Slovenia, for example, many domains have a very high Visibility Index, while in Germany most domains score well below "1". Comparing these values directly would give the false impression that all German domains are poor and all Slovenian domains are exceptionally good – which would be wrong. The Visibility Index should therefore only be compared within the same country.
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The Visibility Index is not available for all countries. In more exotic markets, the tool may return "0", which can quickly create a misleading picture of a site's quality if this metric is considered in isolation.
Domain Authority (DA)
This metric indicates how significant a website is within its subject area. It is made up of various factors such as content quality, inbound links, and domain age. Other factors also play a role, and different analysis tools calculate this KPI somewhat differently – with MOZ's calculation being the most commonly used. Ultimately, it is a useful indicator of how trustworthy a website is.
It is particularly useful because it works across country borders.
Power*Trust (P*T)
This is a KPI used by the tool provider LRT, made up of the product of two metrics:
- Link Power (Power) – How much link power a link from this domain can pass on
- Link Trustworthiness (Trust) – How trustworthy a link from this domain is
Below is an overview of the four possible combinations of Power*Trust:
| Low Trust | High Trust | |
|---|---|---|
| High Power | Short-term Boost | Top Links |
| Low Power | Weak Links | Potential |
Short-term Boost: These links pass on little trust but can provide a short-term push for a page. However, you should not rely exclusively on this type of link.
Weak Links: They have neither trust nor power. These are links that nobody really needs.
Potential: Domains with this distribution enjoy a high level of trust but have a weak link profile themselves. This combination is often found with public authorities or educational institutions. You should definitely build these links if you have the opportunity.
Top Links: These are hard-to-find premium links that offer everything you want for your own website. If you have the opportunity to get such a link, you should take it.
Topic Relevance
According to Google, links are especially valuable when they come from the same thematic context as your own site. This means that even links with weak metrics can be of interest – links you would normally discard. As already hinted at in the section on the Visibility Index, this applies especially to very specific niche sites. So pay attention not just to the KPIs, but also to the thematic context of the domain you want a link from.
Conclusion
It is important to understand that a single metric tells us very little – it is only the combination of all the mentioned KPIs that provides a reliable view of a domain's quality. At Working Digital, we work with all metrics and therefore always have a clear picture of the actual quality of any domain.