There are some changes coming soon to the way Moz calculates the domain authority of websites. As a reminder, Moz has a tool called Link Explorer that we use (along with other third-party tools that measure a similar metric) to calculate “domain authority,” which, in a simple sense, is a measure of how strong a given website is.
Moz recently announced that they are changing the algorithm they use to calculate domain authority, which means there will be some fluctuation in numbers. Their new algorithm will now factor in the amount of spam links a website is receiving (this was previously separated out as a spam score) while also factoring in how well websites are actually ranking. The changes are, in part, intended to help stop people from using link-building schemes to artificially inflate their numbers.
It’s important to keep in mind moving forward that domain authority is just one small measure of how well a site is performing. Moz itself is stating that the number is intended to be a relative measure of how well a site is doing in comparison to its competitors rather than an absolute measure of a site’s strength.
If you have any questions about these changes, please don’t hesitate to ask.