Moz Q&A is closed.
After more than 13 years, and tens of thousands of questions, Moz Q&A closed on 12th December 2024. Whilst we’re not completely removing the content - many posts will still be possible to view - we have locked both new posts and new replies. More details here.
How much domain authority is passed on through a link from a page with low authority?
-
Hello,
Let's say that there is a link to site A from site B. The domain authority of site B is 85, but the link is on a page that has a page authority of only 1. Does much authority get passed along from site B to site A? (Let's assume site A has a domain authority of 35, if that's relevant.)
Thank you!
-
Thanks, Federico.
-
Thank you, Keri!
-
Thank you very much, Dr. Meyers! This was extremely helpful.
-
Unfortunately, Dr. Matt's out of town, so this answer won't be as thorough as I'd like, but the gist of it is that we factor in both DA and PA to some degree. If a site has very high DA but a very low PA (as in your example), we're going to bias somewhat toward the DA, as we believe Google sometimes does (a virtually unknown page on Wikipedia can rank very well, for example). Likewise, a high-PA page on a site with low DA may pass more through the PA, because (hopefully) that page has some legitimate authority.
It's a bit more complex, because DA and PA are related as well, so they do influence each other to some degree. On larger sites, the influence of any single page's PA is small, but the influence can be more obvious on smaller sites.
Putting aside our math, I think a link from a low-authority page on a high-authority site can be worthwhile. Look at directories, like DMOZ. I think it's important to make sure the low-PA page is indexed (some DMOZ pages aren't, because they're buried so deeply in the link structure), and I wouldn't get hung up on a link from a high-DA site. It's ultimately just one link. I wouldn't dismiss it as useless either, though. There's some amount of site/page balance in the mix and Google doesn't rely on only one type of authority.
-
I'm checking with Dr. Matt Peters, head of our Data Science team. It's less about secrecy and more that DA/PA are based on machine learning and have gotten a bit complex. Still, I suspect we can give you a general sense of how DA/PA pass through links. Posting this because I suspect an answer may take a day or two.
-
Well, it is a bit late for regular office hours for most Moz staff, so you may not hear an answer until tomorrow. The answer may also include "remember, what the search engines think is what matters", but you should get an answer with at least some information in the next couple of days.
-
and I am sure Moz will not answer this at all!
-
It is, but no one outside Moz can answer that, there are several metrics that affect authority passing, and I guess that most of those metrics and algos are property of Moz and most likely secret to prevent abuse.
Got a burning SEO question?
Subscribe to Moz Pro to gain full access to Q&A, answer questions, and ask your own.
Browse Questions
Explore more categories
-
Moz Tools
Chat with the community about the Moz tools.
-
SEO Tactics
Discuss the SEO process with fellow marketers
-
Community
Discuss industry events, jobs, and news!
-
Digital Marketing
Chat about tactics outside of SEO
-
Research & Trends
Dive into research and trends in the search industry.
-
Support
Connect on product support and feature requests.
Related Questions
-
Remove page with PA of 69 and 300 root domain links?
Hi We have a few pages within our website which were at one time a focus for us, but due to developing the other areas of the website, they are now defunct (better content elsewhere) and in some ways slightly duplicate so we're merging two areas into one. We have removed the links to the main hub page from our navigation, and were going to 301 this main page to the main hub page of the section which replaces it. However I've just noticed the page due to be removed has a PA of 69 and 15,000 incoming links from 300 root domains. So not bad! It's actually stronger than the page we are 301'ing it to (but not really an option to swap as the URL structure will look messy) With this in mind, is the strategy to redirect still the best or should we keep the page and turn it into a landing page, with links off to the other section? It just feels as though we would be doing this just for the sake of google, im not sure how much decent content we could put on it as we've already done that on the destination page. The incoming links to that page will still be relevant to the new section (they are both v similar hence the merging) Any suggestions welcome, thanks
Technical SEO | | benseb0 -
Is it good to redirect million of pages on a single page?
My site has 10 lakh approx. genuine urls. But due to some unidentified bugs site has created irrelevant urls 10 million approx. Since we don’t know the origin of these non-relevant links, we want to redirect or remove all these urls. Please suggest is it good to redirect such a high number urls to home page or to throw 404 for these pages. Or any other suggestions to solve this issue.
Technical SEO | | vivekrathore0 -
Should I noindex my blog's tag, category, and author pages
Hi there, Is it a good idea to no index tag, category, and author pages on blogs? The tag pages sometimes have duplicate content. And the category and author pages aren't really optimized for any search term. Just curious what others think. Thanks!
Technical SEO | | Rignite0 -
Redirecting root domain to a page based on user login
We have our main URL redirecting non-logged in users to a specific page and logged in users are directed to their dashboard when going to the main URL. We find this to be the most user-friendly, however, this is all being picked up as a 302 redirect. I am trying to advise on the ideal way to accomplish this, but I am not having much luck in my search for information. I believe we are going to put a true homepage at the root domain and simply redirect logged in users as usual when they hit the URL, but I'm still concerned this will cause issues with Google and other search engines. Anyone have experience with domains that need to work in this manner? Thank you! Anna
Technical SEO | | annalytical0 -
404 error - but I can't find any broken links on the referrer pages
Hi, My crawl has diagnosed a client's site with eight 404 errors. In my CSV download of the crawl, I have checked the source code of the 'referrer' pages, but can't find where the link to the 404 error page is. Could there be another reason for getting 404 errors? Thanks for your help. Katharine.
Technical SEO | | PooleyK0 -
Do I need to add canonical link tags to pages that I promote & track w/ UTM tags?
New to SEOmoz, loving it so far. I promote content on my site a lot and am diligent about using UTM tags to track conversions & attribute data properly. I was reading earlier about the use of link rel=canonical in the case of duplicate page content and can't find a conclusive answer whether or not I need to add the canonical tag to these pages. Do I need the canonical tag in this case? If so, can the canonical tag live in the HEAD section of the original / base page itself as well as any other URLs that call that content (that have UTM tags, etc)? Thank you.
Technical SEO | | askotzko1 -
How much authority does a 301 pass to a different domain?
Hi, A client of mine is selling his business to a brand new company. The brand new company will be using a brand new domain (no way to avoid that unfortunately) and the current domain (which has tons of authority, links, shares, tweets, etc.) will not be used. Added to that, the new company will be taking over all the current content with just a few minor changes. (I know, I wish we could use the old domain but we can't.) Obviously, I am redirecting all pages on the current domain to the new domain via 301 redirects on a page by page basis. So, current.com/product-page-x.html redirects to new.com/product-page-x.html. My client and the new company both are asking me how much link juice (and other factors) are passed along to the new domain from the old domain. All I can find is "not the full value" or variants thereof.My experience with 301 redirects in the past has been within a single domain and I've seen some of those pages have decent authority and decent rankings as a result of the 301 (no other optimization work was done or links were added). Are there any studies out there that I'm missing that show how much authority/juice gets passed and/or lost via a 301 redirect? Anybody with a similar issue see any trends in page/domain authority and/or rankings? Thanks for any insights and opinions you have.
Technical SEO | | Matthew_Edgar0 -
Multiple Domains, Same IP address, redirecting to preferred domain (301) -site is still indexed under wrong domains
Due to acquisitions over time and the merging of many microsites into one major site, we currently have 20+ TLD's pointing to the same IP address as our "preferred domain:" for our consolidated website http://goo.gl/gH33w. They are all set up as 301 redirects on apache - including both the www and non www versions. When we launched this consolidated website, (April 2010) we accidentally left the settings of our site open to accept any of our domains on the same IP. This was later fixed but unfortunately Google indexed our site under multiple of these URL's (ignoring the redirects) using the same content from our main website but swapping out the domain. We added some additional redirects on apache to redirect these individual pages pages indexed under the wrong domain to the same page under our main domain http://goo.gl/gH33w. This seemed to help resolve the issue and moved hundreds of pages off the index. However, in December of 2010 we made significant changes in our external dns for our ip addresses and now since December, we see pages indexed under these redirecting domains on the rise again. If you do a search query of : site:laboratoryid.com you will see a few hundred examples of pages indexed under the wrong domain. When you click on the link, it does redirect to the same page but under the preferred domain. So the redirect is working and has been confirmed as 301. But for some reason Google continues to crawl our site and index under this incorrect domains. Why is this? Is there a setting we are missing? These domain level and page level redirects should be decreasing the pages being indexed under the wrong domain but it appears it is doing the reverse. All of these old domains currently point to our production IP address where are preferred domain is also pointing. Could this be the issue? None of the pages indexed today are from the old version of these sites. They only seem to be the new content from the new site but not under the preferred domain. Any insight would be much appreciated because we have tried many things without success to get this resolved.
Technical SEO | | sboelter0