[[["易于理解","easyToUnderstand","thumb-up"],["解决了我的问题","solvedMyProblem","thumb-up"],["其他","otherUp","thumb-up"]],[["没有我需要的信息","missingTheInformationINeed","thumb-down"],["太复杂/步骤太多","tooComplicatedTooManySteps","thumb-down"],["内容需要更新","outOfDate","thumb-down"],["翻译问题","translationIssue","thumb-down"],["示例/代码问题","samplesCodeIssue","thumb-down"],["其他","otherDown","thumb-down"]],["最后更新时间 (UTC):2008-10-01。"],[[["\u003cp\u003eThere's no penalty for unintentional duplicate content; Google focuses on intent and often consolidates similar content under a preferred URL.\u003c/p\u003e\n"],["\u003cp\u003eDuplicate content can impact your site's performance in search results by diluting ranking signals and influencing Google's URL selection.\u003c/p\u003e\n"],["\u003cp\u003eWebsite owners should focus on providing unique, valuable content and utilize tools like sitemaps to manage unintentional duplication.\u003c/p\u003e\n"],["\u003cp\u003eWhile unintentional duplication is usually handled by search engines, deliberate content scraping or replication can lead to penalties.\u003c/p\u003e\n"],["\u003cp\u003eExcessive duplicate content can strain website resources and crawling efficiency, impacting the indexing of other important pages.\u003c/p\u003e\n"]]],["Duplicate content does not incur penalties unless it's intentionally deceptive. Common instances, like multiple URLs for the same content, can affect site performance but don't lead to penalties. Search engines group duplicate URLs, selecting a \"best\" one for display. Webmasters can influence this choice via Sitemaps. Content scraping and thin affiliate content are discouraged. Duplicate content can cause inefficient crawling. Building a site that duplicates content across domains, without adding value, will also make it more difficult to rank.\n"],null,["# Demystifying the \"duplicate content penalty\"\n\nFriday, September 12, 2008\n\n\nDuplicate content. There's just something about it. We\n[keep](/search/blog/2006/12/deftly-dealing-with-duplicate-content)\n[writing](/search/blog/2007/06/duplicate-content-summit-at-smx)\n[about](/search/blog/2007/09/google-duplicate-content-caused-by-url)\n[it](/search/blog/2008/06/duplicate-content-due-to-scrapers), and people keep asking\nabout it. In particular, I still hear a lot of webmasters worrying about whether they may have a\n\"duplicate content penalty.\"\n\n\nLet's put this to bed once and for all, folks: There's no such thing as a \"duplicate content\npenalty.\" At least, not in the way most people mean when they say that.\n\n\nThere are some penalties that are related to the idea of having the same content as another\nsite---for example, if you're scraping content from other sites and republishing it, or if\nyou republish content without adding any additional value. These tactics are clearly outlined\n(and discouraged) in our\n[Webmaster Guidelines](/search/docs/essentials):\n\n- Don't create multiple pages, subdomains, or domains with substantially [duplicate content](/search/docs/advanced/guidelines/duplicate-content).\n- Avoid... \"cookie cutter\" approaches such as affiliate programs with [little or no original content](/search/docs/advanced/guidelines/thin-content).\n- If your site participates in an [affiliate program](/search/docs/essentials/spam-policies#thin-affiliate-pages), make sure that your site adds value. Provide unique and relevant content that gives users a reason to visit your site first.\n\n\n(Note that while scraping content from others is discouraged, having others scrape you is a\ndifferent story;\n[check out this post](/search/blog/2008/06/duplicate-content-due-to-scrapers)\nif you're worried about being scraped.)\n\n\nBut most site owners whom I hear worrying about duplicate content aren't talking about scraping or\ndomain farms; they're talking about things like having multiple URLs on the same domain that point\nto the same content. Like\n`www.example.com/skates.asp?color=black&brand=riedell`\nand `www.example.com/skates.asp?brand=riedell&color=black`. Having this type of\nduplicate content on your site can potentially affect your site's performance, but it doesn't\ncause penalties. From our article on\n[duplicate content](/search/docs/advanced/guidelines/duplicate-content):\n\n\nDuplicate content on a site is not grounds for action on that site unless it appears that the\nintent of the duplicate content is to be deceptive and manipulate search engine results. If your\nsite suffers from duplicate content issues, and you don't follow the advice listed above, we do\na good job of choosing a version of the content to show in our search results.\n\n\nThis type of non-malicious duplication is fairly common, especially since many CMSs don't handle\nthis well by default. So when people say that having this type of duplicate content can affect\nyour site, it's not because you're likely to be penalized; it's simply due to the way that web\nsites and search engines work.\n\n\nMost search engines strive for a certain level of variety; they want to show you ten different\nresults on a search results page, not ten different URLs that all have the same content. To this\nend, Google tries to filter out duplicate documents so that users experience less redundancy. You\ncan find details in\n[this blog post](/search/blog/2007/09/google-duplicate-content-caused-by-url), which\nstates:\n\n1. When we detect duplicate content, such as through variations caused by URL parameters, we group the duplicate URLs into one cluster.\n2. We select what we think is the \"best\" URL to represent the cluster in search results.\n3. We then consolidate properties of the URLs in the cluster, such as link popularity, to the representative URL.\n\nHere's how this could affect you as a webmaster:\n\n- In step 2, Google's idea of what the \"best\" URL is might not be the same as your idea. If you want to have control over whether `www.example.com/skates.asp?color=black&brand=riedell` or `www.example.com/skates.asp?brand=riedell&color=black` gets shown in our search results, you may want to take action to mitigate your duplication. One way of letting us know which URL you prefer is by including the preferred URL in your [Sitemap](/search/docs/crawling-indexing/sitemaps/overview).\n- In step 3, if we aren't able to detect all the duplicates of a particular page, we won't be able to consolidate all of their properties. This may dilute the strength of that content's ranking signals by splitting them across multiple URLs.\n\n\nIn most cases Google does a good job of handling this type of duplication. However, you may also\nwant to consider content that's being duplicated across domains. In particular, deciding to build\na site whose purpose inherently involves content duplication is something you should think twice\nabout if your business model is going to rely on search traffic, unless you can add a lot of\nadditional value for users. For example, we sometimes hear from Amazon.com affiliates who are\nhaving a hard time ranking for content that originates solely from Amazon. Is this because Google\nwants to stop them from trying to sell\n[Everyone Poops](https://www.amazon.com/Everyone-Poops-My-Body-Science/dp/0916291456)?\nNo; it's because *how the heck are they going to outrank Amazon* if they're providing\nthe exact same listing? Amazon has a lot of online business authority (most likely more than\na typical Amazon affiliate site does), and the average Google search user probably wants the\noriginal information on Amazon, unless the affiliate site has added a significant amount of\n[additional value](/search/docs/essentials/spam-policies#thin-affiliate-pages).\n\n\nLastly, consider the effect that duplication can have on your site's bandwidth. Duplicated\ncontent can lead to inefficient crawling: when Googlebot discovers ten URLs on your site, it has\nto crawl each of those URLs before it knows whether they contain the same content (and thus before\nwe can group them as described above). The more time and resources that Googlebot spends crawling\nduplicate content across multiple URLs, the less time it has to get to the rest of your content.\n\n\nIn summary: Having duplicate content can affect your site in a variety of ways; but unless you've\nbeen duplicating deliberately, it's unlikely that one of those ways will be a penalty. This means\nthat:\n\n- You typically don't need to submit a reconsideration request when you're cleaning up innocently duplicated content.\n- If you're a webmaster of beginner-to-intermediate savviness, you probably don't need to put too much energy into worrying about duplicate content, since most search engines have ways of handling it.\n- You can help your fellow webmasters by not perpetuating the myth of duplicate content penalties! The remedies for duplicate content are entirely within your control. Here are some good places to start:\n - [Avoid creating duplicate content](/search/docs/advanced/guidelines/duplicate-content)\n - [Deftly dealing with duplicate content](/search/blog/2006/12/deftly-dealing-with-duplicate-content)\n - [Duplicate content summit at SMX Advanced](/search/blog/2007/06/duplicate-content-summit-at-smx)\n - [Google, duplicate content caused by URL parameters, and you](/search/blog/2007/09/google-duplicate-content-caused-by-url)\n\nPosted by Susan Moskwa, Webmaster Trends Analyst"]]