Domain Authority (DA) is one of the most talked-about numbers in SEO. Here is what it really measures, how to improve it and why it sometimes goes down.
What is Domain Authority?
Domain Authority is a score from 1 to 100 created by Moz that predicts how likely a website is to rank in search results compared with other sites. Higher scores mean a greater ability to rank. It is calculated mainly from the number and quality of websites linking to yours.
The scale is logarithmic, so it is much easier to go from 10 to 20 than from 60 to 70. You can check DA with Moz’s free Link Explorer or the MozBar browser extension.
What is Page Authority?
Page Authority (PA), also from Moz, predicts how well a specific page will rank, on the same 1–100 scale.
Factors that increase Domain Authority
1. Earn quality backlinks
The biggest factor. Links from many different, relevant and trusted websites raise DA far more than lots of links from a few low-quality sites. Earn them with useful content, digital PR, partnerships, guest posts on reputable sites and local citations.
2. Create linkable content
Original research, guides, tools, templates and checklists naturally attract links. If your content is genuinely useful and unique, other websites will reference it.
3. Optimise on-page SEO
Clear title tags, meta descriptions, headings, image alt text and keyword-focused content help your pages rank — and pages that rank attract more links.
4. Build a strong internal linking structure
Link related pages together, especially new posts to and from older ones. Internal links help search engines discover pages, spread link value across your site and help visitors find what they need.
5. Improve page speed and user experience
Fast, mobile-friendly pages with good Core Web Vitals keep visitors engaged and make people more willing to link to and share your content. Aim for pages that load in about 2–3 seconds.
6. Choose a good domain name and keep it
A short, memorable, brand-friendly domain makes it easier for people to remember, mention and link to you. Avoid changing domains unnecessarily — migrations without proper redirects lose link value.
Why Domain Authority decreases
1. You lost backlinks
Links get removed, pages linking to you are deleted or sites go offline. Track lost links and reclaim important ones.
2. Other websites grew faster
DA is relative. If large sites gain many links, the scale shifts and your score can drop even if nothing changed on your site.
3. Moz updated its calculation
Moz periodically updates how DA is calculated and refreshes its link index, which can move scores across the web.
4. Spammy or low-quality links
A link profile full of spammy, irrelevant or paid links signals low quality. Google usually ignores such links, but they add no value and can attract a manual action in serious cases.
5. Thin or poor-quality content
Thin, duplicate or low-value content does not earn links or rankings over time. Focus on quality and usefulness rather than word count.
Frequently asked questions
Does Google use Domain Authority?
No. Domain Authority is a Moz metric. Google uses its own signals, including links, but not Moz’s DA score.
What is a good Domain Authority score?
It is relative. Compare your score with competitors in your niche rather than aiming for a fixed number.
How long does it take to increase Domain Authority?
Usually months, because it depends on earning new quality links and on Moz updating its index.
Can one bad link reduce my Domain Authority?
Not usually. DA reflects your overall link profile; a single low-quality link has little effect, and Google typically ignores spammy links.
