From tomorrow on, it will be exactly 15 days until Yahoo is expected to shut off all API-access to their backlink-database. Those who have followed Microsofts remarks on the matter over the past couple of month, will have noticed that there are no plans to make this database available again, in the future. This means that the principal source for backlink-data will dissapear overnight. Links have been the #1 ranking-signal since the founding days of Google and that this is not going to change anytime soon, even though other signals like user-data or social networking-data are being used. This leaves us – especially me as the Toolbox-operator – with the question of which sources to use in the future?

It should not come as a surprise that I did extensive research on this subject and tested possible alternatives. On the subject of backlink-data there are two vendors that immediately come to mind: Seomoz and Majesticseo. Seomoz is fiddling arround with their own index since 2008: first using Linkscape, now with the Opensiteexplorer as a display-tool. Majesticseo came to be out of a concept of a decentralized searchengine and has, since they not only kept hording links but also started throwing away old links in a segment they call “fresh index”, become a serious competitor to Seomoz.

A comparison between the two that goes deeper than just a subjective evaluation of how each vendors' graphical features look, is actually harder than first expected. So I decided on the following procedure: I gathered up link-metrics for five packets of five domains each (25 domains in all) with both Seomoz and Majesticseo: on the one hand, I compared the absolute amound of links returned as indicator of the size of the data-pool and depth of the crawl, on the other hand I gathered up the domain-pop, meaning the amount of different domains that link to the target-domain, as an indicator for the breadth and diversity of the data. The domain-packets are each made up of 5 domains, belonging to the largest in Germany, five vertical portals, five pages that have something to do with Bonn, five Amazon country-specific subsidiaries as well as 5 SEO-sites. You can see the chart for all the domains and results in Google Docs:



The results have actually surpised me a bit: while Majesticseo clearly comes out on top as far as the absolute number of links are concerned (17 to 8), we have Seomoz who takes home a clear victory as far as domain-popularity is concerned (18 to 7). The problem with this result is this: neither Majesticseo nor Seomoz deliver backlink-data that have both the needed depth and breadth at the same time. Using a combination of both services is not reasonable/possible thanks to the limited amount of API-access and/or the costs associated with it. This means that the question of whether to “buy or build” was answered rather clearly and we went to work on developing our own solution. But more on that next month...