Skip to content
    Moz logo Menu open Menu close
    • Products
      • Moz Pro
      • Moz Pro Home
      • Moz Local
      • Moz Local Home
      • STAT
      • Moz API
      • Moz API Home
      • Compare SEO Products
      • Moz Data
    • Free SEO Tools
      • Domain Analysis
      • Keyword Explorer
      • Link Explorer
      • Competitive Research
      • MozBar
      • More Free SEO Tools
    • Learn SEO
      • Beginner's Guide to SEO
      • SEO Learning Center
      • Moz Academy
      • MozCon
      • Webinars, Whitepapers, & Guides
    • Blog
    • Why Moz
      • Digital Marketers
      • Agency Solutions
      • Enterprise Solutions
      • Small Business Solutions
      • The Moz Story
      • New Releases
    • Log in
    • Log out
    • Products
      • Moz Pro

        Your all-in-one suite of SEO essentials.

      • Moz Local

        Raise your local SEO visibility with complete local SEO management.

      • STAT

        SERP tracking and analytics for enterprise SEO experts.

      • Moz API

        Power your SEO with our index of over 44 trillion links.

      • Compare SEO Products

        See which Moz SEO solution best meets your business needs.

      • Moz Data

        Power your SEO strategy & AI models with custom data solutions.

      Track AI Overviews in Keyword Research
      Moz Pro

      Track AI Overviews in Keyword Research

      Try it free!
    • Free SEO Tools
      • Domain Analysis

        Get top competitive SEO metrics like DA, top pages and more.

      • Keyword Explorer

        Find traffic-driving keywords with our 1.25 billion+ keyword index.

      • Link Explorer

        Explore over 40 trillion links for powerful backlink data.

      • Competitive Research

        Uncover valuable insights on your organic search competitors.

      • MozBar

        See top SEO metrics for free as you browse the web.

      • More Free SEO Tools

        Explore all the free SEO tools Moz has to offer.

      NEW Keyword Suggestions by Topic
      Moz Pro

      NEW Keyword Suggestions by Topic

      Learn more
    • Learn SEO
      • Beginner's Guide to SEO

        The #1 most popular introduction to SEO, trusted by millions.

      • SEO Learning Center

        Broaden your knowledge with SEO resources for all skill levels.

      • On-Demand Webinars

        Learn modern SEO best practices from industry experts.

      • How-To Guides

        Step-by-step guides to search success from the authority on SEO.

      • Moz Academy

        Upskill and get certified with on-demand courses & certifications.

      • MozCon

        Save on Early Bird tickets and join us in London or New York City

      Unlock flexible pricing & new endpoints
      Moz API

      Unlock flexible pricing & new endpoints

      Find your plan
    • Blog
    • Why Moz
      • Digital Marketers

        Simplify SEO tasks to save time and grow your traffic.

      • Small Business Solutions

        Uncover insights to make smarter marketing decisions in less time.

      • Agency Solutions

        Earn & keep valuable clients with unparalleled data & insights.

      • Enterprise Solutions

        Gain a competitive edge in the ever-changing world of search.

      • The Moz Story

        Moz was the first & remains the most trusted SEO company.

      • New Releases

        Get the scoop on the latest and greatest from Moz.

      Surface actionable competitive intel
      New Feature

      Surface actionable competitive intel

      Learn More
    • Log in
      • Moz Pro
      • Moz Local
      • Moz Local Dashboard
      • Moz API
      • Moz API Dashboard
      • Moz Academy
    • Avatar
      • Moz Home
      • Notifications
      • Account & Billing
      • Manage Users
      • Community Profile
      • My Q&A
      • My Videos
      • Log Out

    The Moz Q&A Forum

    • Forum
    • Questions
    • My Q&A
    • Users
    • Ask the Community

    Welcome to the Q&A Forum

    Browse the forum for helpful insights and fresh discussions about all things SEO.

    1. Home
    2. SEO Tactics
    3. Intermediate & Advanced SEO
    4. Why some domains and sub-domains have same DA, but some others don't?

    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.

    Why some domains and sub-domains have same DA, but some others don't?

    Intermediate & Advanced SEO
    3
    3
    1607
    Loading More Posts
    • Oldest to Newest
    • Newest to Oldest
    • Most Votes
    Reply
    • Reply as question
    Log in to reply
    This topic has been deleted. Only users with question management privileges can see it.
    • rayatarh545123
      rayatarh545123 last edited by

      Hi

      I noticed for some blog providers in my country, which provide a sub-domian address for their blogs. the sub-domain authority is exactly as the main domain. Whereas, for some other blog providers  every subdomain has its different and lower authority.

      for example "ffff.blog.ir" and "blog.ir" both have domain authority of 60. It noteworthy to mention that the "ffff.blog.ir" does not even exist!

      This is while mihanblog.com and hfilm.mihanblog.com has diffrent page authority.

      1 Reply Last reply Reply Quote 0
      • dave.kudera
        dave.kudera Staff last edited by

        Hey!

        DA scores are specific to the root domain, we are not taking into account a subdomain.  So even if you search a subdomain that doesn't exist (ffff.blog.ir), DA score is still only relevant to the root domain (blog.ir) which does exist.

        Page Authority on the other hand is specific to the exact page you are searching, so it makes sense that mihanblog.com and hfilm.mihanblog.com would have different page authority scores are they are separate pages.

        Hope that helps, let me know if you have further questions.

        1 Reply Last reply Reply Quote 0
        • effectdigital
          effectdigital last edited by

          Am pretty sure that Moz just unifies DA stats in some circumstances when they have no 'actual' data for the subdomain in question. Sites which are very important, which have a number of sub-domains (but not hundreds or thousands) often render different results for DA metrics. For some blog platforms (blogger is a good example, also "blogname.wordpress.com" WordPress hosted blogs) - they have thousands or hundreds of thousands of sub-domains and Moz can't index all of them

          In these situations, if Moz comes across a subdomain which is well-linked across the web it will separate it out and ascribe unique values. For the rest (of which Moz holds no data), it probably just unifies the DA metric with the root domain

          It's a symptom of an incomplete index of the web. That being said, no one has a complete index of the web - you have to work with what you got

          1 Reply Last reply Reply Quote 2
          • 1 / 1
          • First post
            Last post

          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.

          • See all categories

          Related Questions

          • rastellop

            Does Google ignore content styled with 'display:none'?

            Do you know if an H1 within a div that has a 'display: none' style applied will still be crawled and evaluated by Google? We have that situation on this page on line 136: view-source:https://www.junk-king.com/services/items-we-take/foreclosure-cleanouts Of course we also have an H1 up at the top of the page and are concerned that the second one will cause interference with our SEO efforts. I've seen conflicting and inconclusive information on line - not sure. Thanks for any help.

            Intermediate & Advanced SEO | | rastellop
            0
          • NortonSupportSEO

            Is it possible to have organization markup schema for sub domain ? and how should it look like ?

            Can we have organization markup schema for subdomain ? For example if my main domain is xyz.com and subdomain is sub.xyz.com If i plan to have organization markup schema for subdomain how should it look like ? Should the markup schema must have main domain url or sub domain url in markup schema ? Should it be like this ?

            Intermediate & Advanced SEO | | NortonSupportSEO
            0
          • vtmoz

            What are best page titles for sub-domain pages?

            Hi Moz communtity, Let's say a website has multiple sub-domains with hundreds and thousands of pages. Generally we will be mentioning "primary keyword & "brand name" on every page of website. Can we do same on all pages of sub-domains to increase the authority of website for this primary keyword in Google? Or it gonna end up as negative impact if Google consider as duplicate content being mentioned same keyword and brand name on every page even on website and all pages of sub domains? Thanks

            Intermediate & Advanced SEO | | vtmoz
            0
          • Edward_Sturm

            Why doesn't the Wikipedia homepage have meta tags?

            Why doesn't the Wikipedia homepage have meta tags?

            Intermediate & Advanced SEO | | Edward_Sturm
            0
          • friendoffood

            Alt tag for src='blank.gif' on lazy load images

            I didn't find an answer on a search on this, so maybe someone here has faced this before. I am loading 20 images that are in the viewport and a bit below.  The next 80 images I want to 'lazy-load'.  They therefore are seen by the bot as a blank.gif file.  However, I would like to get some credit for them by giving a description in the alt tag.  Is that a no-no?  If not, do they all have to be the same alt description since the src name is the same?  I don't want to mess things up with Google by being too aggressive, but at the same time those are valid images once they are lazy loaded, so would like to get some credit for them. Thanks!  Ted

            Intermediate & Advanced SEO | | friendoffood
            0
          • Motava

            Other domains hosted on same server showing up in SERP for 1st site's keywords

            For the website in question, the first domain alphabetically on the shared hosting space, strange search results are appearing on the SERP for keywords associated with the site. Here is an example: A search for "unique company name" shows the results: www.uniquecompanyname.com as the top result. But on pages 2 and 3, we are getting results for the same content but for domains hosted on the same server. Here are some examples with the domain name replaced: UNIQUE DOMAIN NAME PAGE TITLE
            ftp.DOMAIN2.com/?action=news&id=63‎
            META DESCRIPTION TEXT UNIQUE DOMAIN NAME PAGE TITLE 2
            www.DOMAIN3.com/?action=news&id=120‎
            META DESCRIPTION TEXT2 UNIQUE DOMAIN NAME PAGE TITLE 2
            www.DOMAIN4.com/?action=news&id=120
            META DESCRIPTION TEXT2 UNIQUE DOMAIN NAME PAGE TITLE 3
            mail.DOMAIN5.com/?action=category&id=17‎
            META DESCRIPTION TEXT3 ns5.DOMAIN6.com/?action=article&id=27‎‎ There are more but those are just some examples. These other domain names being listed are other customer domains on the same VPS shared server. When clicking the result the browser URL still shows the other customer domain name B but the content is usually the 404 page. The page title and meta description on that page is not displayed the same as on the SERP.As far as we can tell, this is the only domain this is occurring for.So far, no crawl errors detected in Webmaster Tools and moz crawl not completed yet.

            Intermediate & Advanced SEO | | Motava
            0
          • JohnW-UK

            Best way to block a sub-domain from being indexed

            Hello, The search engines have indexed a sub-domain I did not want indexed its on old.domain.com and dev.domain.com - I was going to password them but is there a best practice way to block them. My main domain default robots.txt says :- Sitemap: http://www.domain.com/sitemap.xml global User-agent: *
            Disallow: /cgi-bin/
            Disallow: /wp-admin/
            Disallow: /wp-includes/
            Disallow: /wp-content/plugins/
            Disallow: /wp-content/cache/
            Disallow: /wp-content/themes/
            Disallow: /trackback/
            Disallow: /feed/
            Disallow: /comments/
            Disallow: /category//
            Disallow: */trackback/
            Disallow: */feed/
            Disallow: /comments/
            Disallow: /?

            Intermediate & Advanced SEO | | JohnW-UK
            0
          • simon_realbuzz

            Should I 'nofollow' links between my own sites?

            We have five sites which are largely unrelated but for cross-promotional purpose our company wishes to cross link between all our sites, possibly in the footer. I have warned about potential consequences of cross-linking in this way and certainly don't want our sites to be viewed as some sort of 'link ring' if they all link to one another. Just wondering if linking between sites you own really is that much of an issue and whether we should  'nofollow' the links in order to prevent being slapped with any sort of penalty for cross-linking.

            Intermediate & Advanced SEO | | simon_realbuzz
            0

          Get started with Moz Pro!

          Unlock the power of advanced SEO tools and data-driven insights.

          Start my free trial
          Products
          • Moz Pro
          • Moz Local
          • Moz API
          • Moz Data
          • STAT
          • Product Updates
          Moz Solutions
          • SMB Solutions
          • Agency Solutions
          • Enterprise Solutions
          • Digital Marketers
          Free SEO Tools
          • Domain Authority Checker
          • Link Explorer
          • Keyword Explorer
          • Competitive Research
          • Brand Authority Checker
          • Local Citation Checker
          • MozBar Extension
          • MozCast
          Resources
          • Blog
          • SEO Learning Center
          • Help Hub
          • Beginner's Guide to SEO
          • How-to Guides
          • Moz Academy
          • API Docs
          About Moz
          • About
          • Team
          • Careers
          • Contact
          Why Moz
          • Case Studies
          • Testimonials
          Get Involved
          • Become an Affiliate
          • MozCon
          • Webinars
          • Practical Marketer Series
          • MozPod
          Connect with us

          Contact the Help team

          Join our newsletter
          Moz logo
          © 2021 - 2025 SEOMoz, Inc., a Ziff Davis company. All rights reserved. Moz is a registered trademark of SEOMoz, Inc.
          • Accessibility
          • Terms of Use
          • Privacy