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. Large robots.txt file

    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.

    Large robots.txt file

    Intermediate & Advanced SEO
    1
    2
    1010
    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.
    • ThomasHarvey
      ThomasHarvey last edited by

      We're looking at potentially creating a robots.txt with 1450 lines in it. This will remove 100k+ pages from the crawl that are all old pages (I know, the ideal would be to delete/noindex but not viable unfortunately)

      Now the issue i'm thinking is that a large robots.txt will either stop the robots.txt from being followed or will slow our crawl rate down.

      Does anybody have any experience with a robots.txt of that size?

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

        Answered my own questions:

        https://developers.google.com/webmasters/control-crawl-index/docs/robots_txt?csw=1#file-format

        "A maximum file size may be enforced per crawler. Content which is after the maximum file size may be ignored. Google currently enforces a size limit of 500kb."

        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

        • ThomasHarvey

          What do you add to your robots.txt on your ecommerce sites?

          We're looking at expanding our robots.txt, we currently don't have the ability to noindex/nofollow. We're thinking about adding the following: Checkout Basket Then possibly: Price Theme Sortby other misc filters. What do you include?

          Intermediate & Advanced SEO | | ThomasHarvey
          0
        • jmorehouse

          Should I disallow all URL query strings/parameters in Robots.txt?

          Webmaster Tools correctly identifies the query strings/parameters used in my URLs, but still reports duplicate title tags and meta descriptions for the original URL and the versions with parameters. For example, Webmaster Tools would report duplicates for the following URLs, despite it correctly identifying the "cat_id" and "kw" parameters: /Mulligan-Practitioner-CD-ROM
          /Mulligan-Practitioner-CD-ROM?cat_id=87
          /Mulligan-Practitioner-CD-ROM?kw=CROM Additionally, theses pages have self-referential canonical tags, so I would think I'd be covered, but I recently read that another Mozzer saw a great improvement after disallowing all query/parameter URLs, despite Webmaster Tools not reporting any errors. As I see it, I have two options: Manually tell Google that these parameters have no effect on page content via the URL Parameters section in Webmaster Tools (in case Google is unable to automatically detect this, and I am being penalized as a result). Add "Disallow: *?" to hide all query/parameter URLs from Google. My concern here is that most backlinks include the parameters, and in some cases these parameter URLs outrank the original. Any thoughts?

          Intermediate & Advanced SEO | | jmorehouse
          0
        • khi5

          "noindex, follow" or "robots.txt" for thin content pages

          Does anyone have any testing evidence what is better to use for pages with thin content, yet important pages to keep on a website? I am referring to content shared across multiple websites (such as e-commerce, real estate etc). Imagine a website with 300 high quality pages indexed and 5,000 thin product type pages, which are pages that would not generate relevant search traffic. Question goes: Does the interlinking value achieved by "noindex, follow" outweigh the negative of Google having to crawl all those "noindex" pages? With robots.txt one has Google's crawling focus on just the important pages that are indexed and that may give ranking a boost. Any experiments with insight to this would be great. I do get the story about "make the pages unique", "get customer reviews and comments" etc....but the above question is the important question here.

          Intermediate & Advanced SEO | | khi5
          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
        • fablau

          Robots.txt: how to exclude sub-directories correctly?

          Hello here, I am trying to figure out the correct way to tell SEs to crawls this: http://www.mysite.com/directory/ But not this: http://www.mysite.com/directory/sub-directory/ or this: http://www.mysite.com/directory/sub-directory2/sub-directory/... But with the fact I have thousands of sub-directories with almost infinite combinations, I can't put the following definitions in a manageable way: disallow: /directory/sub-directory/ disallow: /directory/sub-directory2/ disallow: /directory/sub-directory/sub-directory/ disallow: /directory/sub-directory2/subdirectory/ etc... I would end up having thousands of definitions to disallow all the possible sub-directory combinations. So, is the following way a correct, better and shorter way to define what I want above: allow: /directory/$ disallow: /directory/* Would the above work? Any thoughts are very welcome! Thank you in advance. Best, Fab.

          Intermediate & Advanced SEO | | fablau
          1
        • Rubix

          Do you add 404 page into robot file or just add no index tag?

          Hi, got different opinion on this so i wanted to double check with your comment is. We've got /404.html page and I was wondering if you would add this page to robot text so it wouldn't be indexed or would you just add no index tag? What would be the best approach? Thanks!

          Intermediate & Advanced SEO | | Rubix
          0
        • fablau

          Is Google indexing Mp3 audio and MIDI music files? Can that cause any duplicate problems?

          Hello, I own virtualsheetmusic.com website and we have several thousands of media files (Mp3 and MIDI files) that potentially Google can index. If that's the case, I am wondering if that could cause any "duplicate" issues of some sort since many of such media files have  exact file names or same meta information inside. Any thoughts about this issue are very welcome! Thank you in advance to anyone.

          Intermediate & Advanced SEO | | fablau
          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

        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.