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.

      NEW Keyword Suggestions by Topic
      Moz Pro

      NEW Keyword Suggestions by Topic

      Learn more
    • 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
    774
    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

            • TheDude

              URL Rewriting Best Practices

              Hey Moz! I’m getting ready to implement URL rewrites on my website to improve site structure/URL readability. More specifically I want to: Improve our website structure by removing redundant directories. Replace underscores with dashes and remove file extensions for our URLs. Please see my example below: Old structure: http://www.widgets.com/widgets/commercial-widgets/small_blue_widget.htm New structure: https://www.widgets.com/commercial-widgets/small-blue-widget I've read several URL rewriting guides online, all of which seem to provide similar but overall different methods to do this. I'm looking for what's considered best practices to implement these rewrites. From what I understand, the most common method is to implement rewrites in our .htaccess file using mod_rewrite (which will find the old URLs and rewrite them according to the rewrites I implement). One question I can't seem to find a definitive answer to is when I implement the rewrite to remove file extensions/replace underscores with dashes in our URLs, do the webpage file names need to be edited to the new format? From what I understand the webpage file names must remain the same for the rewrites in the .htaccess to work. However, our internal links (including canonical links) must be changed to the new URL format. Can anyone shed light on this? Also, I'm aware that implementing URL rewriting improperly could negatively affect our SERP rankings. If I redirect our old website directory structure to our new structure using this rewrite, are my bases covered in regards to having the proper 301 redirects in place to not affect our rankings negatively? Please offer any advice/reliable guides to handle this properly. Thanks in advance!

              Intermediate & Advanced SEO | | TheDude
              0
            • friendoffood

              Attack of the dummy urls -- what to do?

              It occurs to me that a malicious program could set up thousands of links to dummy pages on a website: www.mysite.com/dynamicpage/dummy123 www.mysite.com/dynamicpage/dummy456 etc.. How is this normally handled?  Does a developer have to look at all the parameters to see if they are valid and if not, automatically create a 301 redirect or 404 not found? This requires a table lookup of acceptable url parameters for all new visitors. I was thinking that bad url names would be rare so it would be ok to just stop the program with a message, until I realized someone could intentionally set up links to non existent pages on a site.

              Intermediate & Advanced SEO | | friendoffood
              1
            • J_Sinclair

              How to deal with URLs and tabbed content

              Hi All, We're currently redesigning a website for a new home developer and we're trying to figure out the best way to deal with tabbed content in the URL structure. The design of the site at the moment will have a page for a development and within that you can select your house type, then when on the house type page there will be tabs displayed for the user to see things like the plot map, availability and pricing, specifications, etc. The way our development team are looking at handling this is for the URL to use a hashtag or a query string at the end of it so we can still land users on these specific tabs for PPC for example. My question is really, has anyone had any experience with this? Any recommendations on how to best display the urls for SEO? Thanks

              Intermediate & Advanced SEO | | J_Sinclair
              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
            • JohnPeters

              Strange URLs, how do I fix this?

              I've just check Majestic and have seen around 50 links coming from one of my other sites. The links all look like this: http://www.dwww.mysite.com
              http://www.eee.mysite.com
              http://www.w.mysite.com The site these links are coming from is a html site. Any ideas whats going on or a way to get rid of these urls? When I visit the strange URLs such as http://www.dwww.mysite.com, it shows the home page of http://www.mysite.com. Is there a way to redirect anything like this back to the home page?

              Intermediate & Advanced SEO | | JohnPeters
              0
            • monster99

              How to Disallow Tag Pages With Robot.txt

              Hi i have a site which i'm dealing with that has tag pages for instant - http://www.domain.com/news/?tag=choice How can i exclude these tag pages (about 20+ being crawled and indexed by the search engines with robot.txt Also sometimes they're created dynamically so i want something which automatically excludes tage pages from being crawled and indexed. Any suggestions? Cheers, Mark

              Intermediate & Advanced SEO | | monster99
              0
            • gregelwell

              Could you use a robots.txt file to disalow a duplicate content page from being crawled?

              A website has duplicate content pages to make it easier for users to find the information from a couple spots in the site navigation. Site owner would like to keep it this way without hurting SEO. I've thought of using the robots.txt file to disallow search engines from crawling one of the pages. Would you think this is a workable/acceptable solution?

              Intermediate & Advanced SEO | | gregelwell
              0
            • AU-SEO

              Brackets in a URL String

              Was talking with a friend about this the other day. Do Brackets and or Braces in a URL string impact SEO? (I know short human readable etc... but for the sake of conversation has anyone relaised any impacts of these particular Characters in a URL?

              Intermediate & Advanced SEO | | AU-SEO
              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
            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.