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. 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
    816
    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

            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

            • Jackson21

              Changing Url Removes Backlink

              Hello MOZ Community, I have question regarding Bad Backlink Removal. My Site's Post's Image got 4 to 5k backlinks from unknown sites and also their is no contact details on their site so that i can contact them to remove. So, I have an idea for which i want suggestion " If I change the url that receieves backlinks" does this will remove backlinks? For Example: https://example.com/test/ got 5k backlinks if I change this url to https://examplee.com/test-failed/ does this will remove those 5k backlinks? If not then How Can I remove those Backlinks? I Know about disavow but this takes time.

              Intermediate & Advanced SEO | | Jackson21
              0
            • 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
            • jayoliverwright

              Duplicate URLs ending with #!

              Hi guys, Does anyone know why a site can contain duplicate URLs ending with hastag & exclamation mark e.g. https://site.com.au/#! We are finding a lot of these URLs (as duplicates) and i was wondering what they are from developer standpoint? And do you think it's worth the time and effort adding a rel canonical tag or 301 to these URLs eventhough they're not getting indexed by Google? Cheers, Chris

              Intermediate & Advanced SEO | | jayoliverwright
              0
            • MiguelSalcido

              Linking to URLs With Hash (#) in Them

              How does link juice flow when linking to URLs with the hash tag in them? If I link to this page, which generates a pop-over on my homepage that gives info about my special offer, where will the link juice go to? homepage.com/#specialoffer Will the link juice go to the homepage? Will it go nowhere? Will it go to the hash URL above? I'd like to publish an annual/evergreen sort of offer that will generate lots of links. And instead of driving those links to homepage.com/offer, I was hoping to get that link juice to flow to the homepage, or maybe even a product page, instead. And just updating the pop over information each year as the offer changes. I've seen competitors do it this way but wanted to see what the community here things in terms of linking to URLs with the hash tag in them. Can also be a use case for using hash tags in URLs for tracking purposes maybe?

              Intermediate & Advanced SEO | | MiguelSalcido
              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
            • browndoginteractive

              Avoiding Duplicate Content with Used Car Listings Database: Robots.txt vs Noindex vs Hash URLs (Help!)

              Hi Guys, We have developed a plugin that allows us to display used vehicle listings from a centralized, third-party database. The functionality works similar to autotrader.com or cargurus.com, and there are two primary components: 1. Vehicle Listings Pages: this is the page where the user can use various filters to narrow the vehicle listings to find the vehicle they want.
              2. Vehicle Details Pages: this is the page where the user actually views the details about said vehicle. It is served up via Ajax, in a dialog box on the Vehicle Listings Pages. Example functionality:  http://screencast.com/t/kArKm4tBo The Vehicle Listings pages (#1), we do want indexed and to rank. These pages have additional content besides the vehicle listings themselves, and those results are randomized or sliced/diced in different and unique ways. They're also updated twice per day. We do not want to index #2, the Vehicle Details pages, as these pages appear and disappear all of the time, based on dealer inventory, and don't have much value in the SERPs. Additionally, other sites such as autotrader.com, Yahoo Autos, and others draw from this same database, so we're worried about duplicate content. For instance, entering a snippet of dealer-provided content for one specific listing that Google indexed yielded 8,200+ results:  Example Google query. We did not originally think that Google would even be able to index these pages, as they are served up via Ajax. However, it seems we were wrong, as Google has already begun indexing them. Not only is duplicate content an issue, but these pages are not meant for visitors to navigate to directly! If a user were to navigate to the url directly, from the SERPs, they would see a page that isn't styled right. Now we have to determine the right solution to keep these pages out of the index:  robots.txt, noindex meta tags, or hash (#) internal links. Robots.txt Advantages: Super easy to implement Conserves crawl budget for large sites Ensures crawler doesn't get stuck. After all, if our website only has 500 pages that we really want indexed and ranked, and vehicle details pages constitute another 1,000,000,000 pages, it doesn't seem to make sense to make Googlebot crawl all of those pages. Robots.txt Disadvantages: Doesn't prevent pages from being indexed, as we've seen, probably because there are internal links to these pages. We could nofollow these internal links, thereby minimizing indexation, but this would lead to each 10-25 noindex internal links on each Vehicle Listings page (will Google think we're pagerank sculpting?) Noindex Advantages: Does prevent vehicle details pages from being indexed Allows ALL pages to be crawled (advantage?) Noindex Disadvantages: Difficult to implement (vehicle details pages are served using ajax, so they have no tag. Solution would have to involve X-Robots-Tag HTTP header and Apache, sending a noindex tag based on querystring variables, similar to this stackoverflow solution. This means the plugin functionality is no longer self-contained, and some hosts may not allow these types of Apache rewrites (as I understand it) Forces (or rather allows) Googlebot to crawl hundreds of thousands of noindex pages.  I say "force" because of the crawl budget required.  Crawler could get stuck/lost in so many pages, and my not like crawling a site with 1,000,000,000 pages, 99.9% of which are noindexed. Cannot be used in conjunction with robots.txt. After all, crawler never reads noindex meta tag if blocked by robots.txt Hash (#) URL Advantages: By using for links on Vehicle Listing pages to Vehicle Details pages (such as "Contact Seller" buttons), coupled with Javascript, crawler won't be able to follow/crawl these links.  Best of both worlds:  crawl budget isn't overtaxed by thousands of noindex pages, and internal links used to index robots.txt-disallowed pages are gone. Accomplishes same thing as "nofollowing" these links, but without looking like pagerank sculpting (?) Does not require complex Apache stuff Hash (#) URL Disdvantages: Is Google suspicious of sites with (some) internal links structured like this, since they can't crawl/follow them? Initially, we implemented robots.txt--the "sledgehammer solution." We figured that we'd have a happier crawler this way, as it wouldn't have to crawl zillions of partially duplicate vehicle details pages, and we wanted it to be like these pages didn't even exist. However, Google seems to be indexing many of these pages anyway, probably based on internal links pointing to them. We could nofollow the links pointing to these pages, but we don't want it to look like we're pagerank sculpting or something like that. If we implement noindex on these pages (and doing so is a difficult task itself), then we will be certain these pages aren't indexed. However, to do so we will have to remove the robots.txt disallowal, in order to let the crawler read the noindex tag on these pages. Intuitively, it doesn't make sense to me to make googlebot crawl zillions of vehicle details pages, all of which are noindexed, and it could easily get stuck/lost/etc. It seems like a waste of resources, and in some shadowy way bad for SEO. My developers are pushing for the third solution:  using the hash URLs. This works on all hosts and keeps all functionality in the plugin self-contained (unlike noindex), and conserves crawl budget while keeping vehicle details page out of the index (unlike robots.txt). But I don't want Google to slap us 6-12 months from now because it doesn't like links like these (). Any thoughts or advice you guys have would be hugely appreciated, as I've been going in circles, circles, circles on this for a couple of days now. Also, I can provide a test site URL if you'd like to see the functionality in action.

              Intermediate & Advanced SEO | | browndoginteractive
              0
            • Milian

              Robots.txt, does it need preceding directory structure?

              Do you need the entire preceding path in robots.txt for it to match? e.g: I know if i add Disallow: /fish to robots.txt it will block /fish
              /fish.html
              /fish/salmon.html
              /fishheads
              /fishheads/yummy.html
              /fish.php?id=anything But would it block?: en/fish
              en/fish.html
              en/fish/salmon.html
              en/fishheads
              en/fishheads/yummy.html
              **en/fish.php?id=anything (taken from Robots.txt Specifications)** I'm hoping it actually wont match, that way writing this particular robots.txt will be much easier! As basically I'm wanting to block many URL that have BTS- in such as: http://www.example.com/BTS-something
              http://www.example.com/BTS-somethingelse
              http://www.example.com/BTS-thingybob But have other pages that I do not want blocked, in subfolders that also have BTS- in, such as: http://www.example.com/somesubfolder/BTS-thingy
              http://www.example.com/anothersubfolder/BTS-otherthingy Thanks for listening

              Intermediate & Advanced SEO | | Milian
              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

            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