If you were an SEO professional five or more years ago, one of the most important metrics you wanted to track was the PageRank of your site. PR was a huge indicator of success and quality in search performance, and it was one of the core influencers of Google search ranking.

Over time, Google began to deprecate PageRank, making it less and less valuable as a whole. The factors that influenced it are still mostly important, but the number itself is much less valuable. The final straw has come slowly over the last couple years, as Google ceased updating PageRank as seen through the Google Toolbar. While the statistic is still in use internally, there’s no modern way to track it.

One of the metrics that has come up to replace it is Domain Authority, as created, pioneered and maintained by Moz.

What is Domain Authority?

Moz began life as far back as 1981, though it was a very different company at the time; a marketing company run by the mother of the Moz founder, Rand Fishkin. It wasn’t until 2004 when Rand himself created SEOMoz as a site to host SEO thoughts, discussions, and discoveries. In the eleven years since, it has grown to become one of the largest and most authoritative SEO resources on the web. It has tracked Google and the techniques, both black and white, that influence search ranking. They rebranded as Moz some time later.

Domain Authority was a ranking system Moz created as a way to rank and compare websites. It’s a complex algorithm, though not as complex as Google’s ranking itself, and it’s a fairly accurate indication of how you stand up against other sites.

The key to remember about Domain Authority is that it’s best used as a comparison. It’s a ranking on a scale of 1 to 100, with 100 being the best – a perfect score – and 1 being a poor site with nothing going for it. It’s also a logarithmic scale. Growing from a 30 to a 40 is much, much easier than growing from a 70 to a 75. Growing from a 90 to a 91 is even harder than going from 1 to 50.

While Domain Authority can be used as a measure of SEO success, it’s a very hard metric to influence. It’s better used as a comparison of static features; that is, if you stripped away the variables that make search ranking fickle and left your site with just the based, fixed factors, Domain Authority would more accurately represent your ranking. A site with lower Domain Authority than your site can out-rank you, but you have firmer ground to stand on to surpass them.

What Makes Up Domain Authority

Moz is, understandably, unwilling to share all of what goes into Domain Authority. However, they do state a few of the factors, to give you an idea of what’s part of the system and what isn’t. Here’s what we know:

  • MozRank is calculated. MozRank is one of the unique metrics Moz tracks, which is based off the link profile of your domain. It’s calculated based on the number of links pointing at your page, measuring the quantity and quality of those links. Quality is factored heavily; a thousand low quality links won’t have nearly the beneficial effect of one high quality link. It’s measured on a scale of 0 to 10, with the Internet average residing around 3.
  • MozTrust is also calculated. MozTrust is a sort of Six Degrees of Separation game, played with quality link seeds. Moz identifies trusted websites, like Google themselves, .edu sites, and .gov sites. They then measure how many degrees away from these seeds you are, in terms of links. If a .gov site links to site A, which links to site B, which links to site C, which links to you, it’s a four-step separation. If site A linked to you instead, you would have a higher MozTrust rank.
  • The websites your page links to are calculated. It can be detrimental to link to spam sites, even if you’re following the link and using the page as a negative example.
  • Domain registration information is calculated. If you own ten websites and all of them have the same contact information, Moz will compare the quality of each site. If six of those ten sites are spam sites, the other four sites will suffer.
  • Domain age is considered. The older your domain is the better. The longer you’ve controlled it, the better.

This is just a small selection, unfortunately. Rand has stated that there are 40 or more factors that go into calculating Domain Authority, though few of them are actually public. Most data on how to influence Domain Authority comes from experimentation and monitoring.

Page Authority

There’s another Moz-tracked metric floating around, and it’s very similar. It’s called Page Authority, and it’s very similar to Domain Authority. The only difference is that Page Authority considers every page on your site individually, based on its own merits. Domain Authority is an aggregate score that considers your entire website as a whole. You might have some individual pages that have low scores, but have a high overall Domain Authority; that’s fine.

Page Authority is only useful in a few side cases, where you want to keep track of how individual pages are performing in comparison to one another. Think of it as another tool for split-testing and you’ll have the right idea.

Measuring Domain Authority

There are two primary ways to check the Domain Authority of your site. The first, and most used, is to just go to Moz’s Open Site Explorer. You can find the OSE here. It has an index of over 400 billion URLs across nearly 400 million root domains, and it indexes over 2 trillion links. That’s a lot of data, when every link is a relationship between two sites involving quality measurements.

The Open Site Explorer includes quite a bit of information in addition to Domain Authority. For example, you can see the most recently discovered links and content. You can see the top pages on your site, and the worst. You can see a listing of your linking domains, like a backlink checker. There’s an anchor text analyzer and a link metric comparison. There’s even a new spam analysis readout. The only downside is that many of the features are gated behind a paid account at Moz.

If you’re looking for a more streamlined, quick way to see your Domain Authority without having to use a site or filter through forms all the time, you can just use the Moz toolbar. The MozBar is found here, and it allows you to see rankings for any site you happen to be browsing.

How to Influence Domain Authority

Now we get to the meat of the issue; how can you influence your Domain Authority to improve it? A higher Domain Authority is an indication of a stronger foundation, a stronger presence, and more potential to rank higher with Google.

Before we begin, though, bear in mind that most of these tips will require at least some amount of work. Domain Authority is a measurement of trust, age, and quality. Some of it isn’t anything you can influence, and what you can influence is difficult to do so. That’s by design. Moz didn’t want anyone to be able to game the algorithm, so they made it difficult to sway one way or another.

So, what can you do?

Pay for your domain in advance. If your domain is getting close to expiring, it’s a slight loss of confidence in your site. No one likes visiting a site they enjoy, only to find a domain expiration notice. It’s a minor factor in Domain Authority calculations, but it/s also incredibly cheap and easy to fix. Just pay for your domain registration for 2-5 years in advance, and you’re good to go.

Build links to your site. Domain Authority is almost entirely a calculation of the quality and quantity of the links coming into your site from elsewhere. You want more links, and whenever possible, you want links from high-quality sites. Start with links from industry authorities and look for opportunities to get your links into high authority generalist sites. If you can find a relevant place to link to yourself in Wikipedia, that’s an easy authority link to get.

You can also try out some broken link building. Look for .gov and .edu sites that have something to do with your industry. Further, look for older reference pages on those sites, and look for links that lead to content that used to exist but is now gone. Identify the content you have that fits the purpose, or write custom content for the purpose. Send a message to whoever maintains the site, through their contact email or through connections you find elsewhere. Let them know that the X link on the Y page is broken and that your link is a valid replacement. It doesn’t always work, but sometimes you can get a decent link through this method.

Expand your link sources. Domain Authority likes it when you have a lot of high-quality links, but it’s better to have 50 high-quality links from 2 authority pages than 100 quality links from 1 page. A distribution means you’re more likely to be a real authority rather than making a deal with a site owner for a link.

Remove bad incoming links. In addition to being a Google factor, negative links are a Domain Authority factor. They aren’t a huge influence to Domain Authority – DA is less susceptible to Negative SEO than Google ranking – but they can still drag you down, particularly when left unchecked. Pull your backlink profile through the Open Site Explorer or another tool, and identify low-quality links. You can then use some tools or elbow grease to get them removed.

Remove bad outgoing links. Domain Authority actually places a lot of emphasis on the sites you link out to in addition to the sites that link to you. You don’t want to link out to spam sites, because that’s what other spam sites do to try to increase their overall reputation in a circular mishmash of links that ideally tries to get one site ranked to pull up the rest. If you look like that one site, you’re painting a target on your head. If you absolutely must use a spam site as an example, type out the URL but don’t link to it, or just take a screenshot.

Work on your on-site SEO. Some specific suggestions might include updating and using a sitemap file, optimizing your meta title and description fields, using an appropriate heading hierarchy throughout your posts, and using index tags on pages that don’t need to be indexed. Another more recent on-site search factor is page loading speed, so you can work to speed up your load times. This might mean getting a faster web host, or it might just mean removing a few widgets and scripts that run poorly.

Boost your social signals. Moz pays a lot more attention to social signals, specifically shares and retweets, than Google themselves do. Every link from a site like Facebook, Twitter, LinkedIn, or Google+ is a link from an authority site. Comments and likes are almost as valuable and help your marketing in other ways.

If necessary, you might need to do an overhaul of your internal site structure. It’s typically a good idea to use a sensible tree organization for your site, with categories and posts within them. It’s also a good idea to use human-readable URLs rather than URLs made out of code or timestamps.

Use a variety of different anchor texts when linking, both internally and externally. Avoid using exact keywords as links. While you’re at it, shoot for an optimal number of links per page. Remember that your navigation links count! I recommend 2-4 links per thousand words, though that’s not a hard limit. You can go over it without issues, as long as you’re not linking every two sentences. Link when it’s necessary.

Expand your content marketing efforts. Build your brand with skillful guest posts throughout industry authority sites. You might not get a link with that post, and even if you do, it might not be valuable. The benefit comes from the owner of that site knowing and recognizing you, and linking to your site on their own later. It’s the start of a relationship, not a fire-and-forget link building solution.

You can also work on blog commenting, in a legitimate and valuable way. Become a prolific commenter in your industry, leaving insight and value wherever you pass. Sometimes you’ll even have relevant content you can leave in the comments. If possible, write a response or rebuttal posts and leave them in links in the comments as well.

As with any sort of SEO, the current best way to get ahead is to create more content. The more content you have of high quality, the more chances you have for people to link to you. It’s no coincidence that many of the highest authority sites have constant content streams that always have something new for a user to read.

Give it time. Domain Authority is very hard to budge, and the higher your ranking is, the harder it is to move. You might be making a lot of progress, but the difference between 80.01 and 80.99 is invisible as far as the ranking is concerned. Your efforts are not in vain! All of the changes you’re making are also useful for Google ranking, user experience enhancements, and conversion rates.

When Are You Done?

So what’s a good ranking to aspire to? Sites like Facebook and Google are obviously 100 out of 100, but aspiring to be the next Google is simply unrealistic. Meanwhile some old, disused and hardly useful sites are in the mid-20s or 30s. Moz itself only has a 94, for that matter.

Really, I can’t give you a good number to aspire towards. What you should do is use the Open Site Explorer to check out your immediate competition. What is their DA ranking, and what is yours? Aspire to be better than they are, and then some. Keep growing! The more time and effort you put in, the better off you’ll be.