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
    • 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. Block session id URLs with robots.txt

    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.

    Block session id URLs with robots.txt

    Intermediate & Advanced SEO
    3
    4
    814
    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.
    • Mat_C
      Mat_C Subscriber last edited by

      Hi,

      I would like to block all URLs with the parameter '?filter=' from being crawled by including them in the robots.txt.

      Which directive should I use:

      User-agent: *
      Disallow: ?filter=

      or

      User-agent: *
      Disallow: /?filter=

      In other words, is the forward slash in the beginning of the disallow directive necessary?

      Thanks!

      1 Reply Last reply Reply Quote 1
      • Mat_C
        Mat_C Subscriber @Martijn_Scheijbeler last edited by

        Hi Martijn,

        Thanks for the answer. Regarding the forward slash in the beginning, is it necessary to use this?

        In the robots text from Zalando for example, you can see that they don't use it for a lot of filters.

        1 Reply Last reply Reply Quote 0
        • Martijn_Scheijbeler
          Martijn_Scheijbeler @jasongmcmahon last edited by

          Uhh, that's not what the requester is looking for and could actually cause tons of problems if you would apply this on a site that you're unaware of. I would always go with the most limiting robots.txt that you can and in this case, I would go with: /?filter=

          Mat_C 1 Reply Last reply Reply Quote 1
          • jasongmcmahon
            jasongmcmahon last edited by

            Hi,

            The following should suffice as it will black any URL with a "?" in it

            User-agent: *
            Disallow: /*?
            
            Martijn_Scheijbeler 1 Reply Last reply Reply Quote 0
            • 1 / 1
            • First post
              Last post

            Got a burning SEO question?

            Subscribe to Moz Pro to gain full access to Q&A, answer questions, and ask your own.


            Start my free trial


            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

            • AspenFasteners

              What happens to crawled URLs subsequently blocked by robots.txt?

              We have a very large store with 278,146 individual product pages. Since these are all various sizes and packaging quantities of less than 200 product categories my feeling is that Google would be better off making sure our category pages are indexed. I would like to block all product pages via robots.txt until we are sure all category pages are indexed, then unblock them. Our product pages rarely change, no ratings or product reviews so there is little reason for a search engine to revisit a product page. The sales team is afraid blocking a previously indexed product page will result in in it being removed from the Google index and would prefer to submit the categories by hand, 10 per day via requested crawling. Which is the better practice?

              Intermediate & Advanced SEO | | AspenFasteners
              1
            • Davit1985

              My url disappeared from Google but Search Console shows indexed. This url has been indexed for more than a year. Please help!

              Super weird problem that I can't solve for last 5 hours. One of my urls: https://www.dcacar.com/lax-car-service.html Has been indexed for more than a year and also has an AMP version, few hours ago I realized that it had disappeared from serps. We were ranking on page 1 for several key terms. When I perform a search "site:dcacar.com " the url is no where to be found  on all 5 pages. But when I check my Google Console it shows as indexed I requested to index again but nothing changed. All other 50 or so urls are not effected at all, this is the only url that has gone missing can someone solve this mystery for me please. Thanks a lot in advance.

              Intermediate & Advanced SEO | | Davit1985
              0
            • binhlai

              If my website do not have a robot.txt file, does it hurt my website ranking?

              After a site audit, I find out that my website don't have a robot.txt. Does it hurt my website rankings? One more thing, when I type mywebsite.com/robot.txt, it automatically redirect to the homepage. Please help!

              Intermediate & Advanced SEO | | binhlai
              0
            • peteboyd

              URL Injection Hack - What to do with spammy URLs that keep appearing in Google's index?

              A website was hacked (URL injection) but the malicious code has been cleaned up and removed from all pages. However, whenever we run a site:domain.com in Google, we keep finding more spammy URLs from the hack. They all lead to a 404 error page since the hack was cleaned up in the code. We have been using the Google WMT Remove URLs tool to have these spammy URLs removed from Google's index but new URLs keep appearing every day. We looked at the cache dates on these URLs and they are vary in dates but none are recent and most are from a month ago when the initial hack occurred. My question is...should we continue to check the index every day and keep submitting these URLs to be removed manually? Or since they all lead to a 404 page will Google eventually remove these spammy URLs from the index automatically? Thanks in advance Moz community for your feedback.

              Intermediate & Advanced SEO | | peteboyd
              0
            • IceIcebaby

              Baidu Spider appearing on robots.txt

              Hi, I'm not too sure what to do about this or what to think of it. This magically appeared in my companies robots.txt file (literally magically appeared/text is below) User-agent: Baiduspider
              User-agent: Baiduspider-video
              User-agent: Baiduspider-image
              Disallow: / I know that Baidu is the Google of China, but I'm not sure why this would appear in our robots.txt all of a sudden. Should I be worried about a hack? Also, would I want to disallow Baidu from crawling my companies website? Thanks for your help,
              -Reed

              Intermediate & Advanced SEO | | IceIcebaby
              0
            • YairSpolter

              Block in robots.txt instead of using canonical?

              When I use a canonical tag for pages that are variations of the same page, it basically means that I don't want Google to index this page. But at the same time, spiders will go ahead and crawl the page. Isn't this a waste of my crawl budget? Wouldn't it be better to just disallow the page in robots.txt and let Google focus on crawling the pages that I do want indexed? In other words, why should I ever use rel=canonical as opposed to simply disallowing in robots.txt?

              Intermediate & Advanced SEO | | YairSpolter
              0
            • RikkiD22

              Recovering from robots.txt error

              Hello, A client of mine is going through a bit of a crisis. A developer (at their end) added Disallow: / to the robots.txt file. Luckily the SEOMoz crawl ran a couple of days after this happened and alerted me to the error. The robots.txt file was quickly updated but the client has found the vast majority of their rankings have gone. It took a further 5 days for GWMT to file that the robots.txt file had been updated and since then we have "Fetched as Google" and "Submitted URL and linked pages" in GWMT. In GWMT it is still showing that that vast majority of pages are blocked in the "Blocked URLs" section, although the robots.txt file below it is now ok. I guess what I want to ask is: What else is there that we can do to recover these rankings quickly? What time scales can we expect for recovery? More importantly has anyone had any experience with this sort of situation and is full recovery normal? Thanks in advance!

              Intermediate & Advanced SEO | | RikkiD22
              0
            • AndrewY

              Blocking Dynamic URLs with Robots.txt

              Background: My e-commerce site uses a lot of layered navigation and sorting links.  While this is great for users, it ends up in a lot of URL variations of the same page being crawled by Google.  For example, a standard category page: www.mysite.com/widgets.html ...which uses a "Price" layered navigation sidebar to filter products based on price also produces the following URLs which link to the same page: http://www.mysite.com/widgets.html?price=1%2C250 http://www.mysite.com/widgets.html?price=2%2C250 http://www.mysite.com/widgets.html?price=3%2C250 As there are literally thousands of these URL variations being indexed, so I'd like to use Robots.txt to disallow these variations. Question: Is this a wise thing to do?  Or does Google take into account layered navigation links by default, and I don't need to worry. To implement, I was going to do the following in Robots.txt: User-agent: * Disallow: /*? Disallow: /*= ....which would prevent any dynamic URL with a '?" or '=' from being indexed.  Is there a better way to do this, or is this a good solution? Thank you!

              Intermediate & Advanced SEO | | AndrewY
              1

            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

            Looks like your connection to Moz was lost, please wait while we try to reconnect.