Over 300 SEO Issues & How To Fix Them - Screaming Frog
Issues
Over 300 SEO issues, warnings and opportunities
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The Screaming Frog SEO Spider identifies over 300 SEO issues, warnings and opportunities that can be seen in the ‘Issues’ tab of the app.
- Issues are an error or issue that should ideally be fixed.
- Warnings are not necessarily an issue, but should be checked – and potentially fixed.
- Opportunities are ‘potential’ areas for optimisation and improvement.
Priorities are based upon potential impact that may require more attention, rather than definitive action – from broadly accepted SEO best practice. They are not hard rules for what should be prioritised in your SEO strategy, or must be ‘fixed’ in your SEO audit as they lack context.
Issues provide direction to users who can make sense of the data and interpret it into appropriate prioritised actions relevant to each unique business, website and objectives. Our issue guidance is handwritten by professional SEOs, not AI. The full list of issues are listed below.
Types of Issues
Issue
Warning
Opportunity
Issue Priorities
High
Medium
Low
Response Codes Security URL Page Titles Meta Description H1 H2 Content Images Canonicals Pagination Directives Hreflang JavaScript Links AMP Structured Data Sitemaps PageSpeed Mobile Accessibility Analytics Search Console Validation
Response Codes
HTTP response status codes indicate whether an HTTP request made during a crawl has been successfully completed. Find issues related to URLs that are blocked from being crawled, return a no response, redirect, client or server error.
Learn More About Response Codes Issues
Internal No Response](/content/seo-spider/issues/response-codes/internal-no-response/index.html) Internal Client Error (4XX)](/content/seo-spider/issues/response-codes/internal-client-error-4xx/index.html) Internal Server Error (5XX)](/content/seo-spider/issues/response-codes/internal-server-error-5xx/index.html) Internal Redirect Loop](/content/seo-spider/issues/response-codes/internal-redirect-loop/index.html)
Learn More About Response Codes Warnings
Internal Blocked by Robots.txt](/content/seo-spider/issues/response-codes/internal-blocked-by-robots-txt/index.html) Internal Blocked Resource](/content/seo-spider/issues/response-codes/internal-blocked-resource/index.html) Internal Redirect Chain](/content/seo-spider/issues/response-codes/internal-redirect-chains/index.html) External Blocked Resource](/content/seo-spider/issues/response-codes/external-blocked-resource/index.html) Internal Redirection (3XX)](/content/seo-spider/issues/response-codes/internal-redirection-3xx/index.html) Internal Redirection (Meta Refresh)](/content/seo-spider/issues/response-codes/internal-redirection-meta-refresh/index.html) Internal Redirection (HTTP Refresh)](/content/seo-spider/issues/response-codes/internal-redirection-http-refresh/index.html) Internal Redirection (JavaScript)](/content/seo-spider/issues/response-codes/internal-redirection-javascript/index.html) External No Response](/content/seo-spider/issues/response-codes/external-no-response/index.html) External Client Error (4XX)](/content/seo-spider/issues/response-codes/external-client-error-4xx/index.html) External Server Error (5XX)](/content/seo-spider/issues/response-codes/external-server-error-5xx/index.html)
Security
Website security is important to protect users and reduce risk from common threats. Find issues related to basic security best practices, such as HTTPS, mixed content, and HTTP security headers.
Learn More About Security Issues
HTTP URLs](/content/seo-spider/issues/security/http-urls/index.html) Mixed Content](/content/seo-spider/issues/security/mixed-content/index.html) Form URL Insecure](/content/seo-spider/issues/security/form-url-insecure/index.html) Form On HTTP URL](/content/seo-spider/issues/security/form-on-http-url/index.html)
Learn More About Security Warnings
Missing HSTS Header](/content/seo-spider/issues/security/missing-hsts-header/index.html) Unsafe Cross Origin Links](/content/seo-spider/issues/security/unsafe-cross-origin-links/index.html) Protocol-Relative Resource Links](/content/seo-spider/issues/security/protocol-relative-resource-links/index.html) Missing Content-Security-Policy Header](/content/seo-spider/issues/security/missing-content-security-policy-header/index.html) Missing X-Content-Type-Options Header](/content/seo-spider/issues/security/missing-x-content-type-options-header/index.html) Missing X-Frames-Options Header](/content/seo-spider/issues/security/missing-x-frames-options-header/index.html) Missing Secure Referrer-Policy Header](/content/seo-spider/issues/security/missing-secure-referrer-policy-header/index.html) Bad Content Type](/content/seo-spider/issues/security/bad-content-type/index.html)
URL
Ensuring a website has logical and relevant URLs is vital for users and search engines in understanding website structure, and the content of a page. Find issues non-optimal formats, or URLs that shouldn't be discoverable.
Learn More About URL Issues
Multiple Slashes](/content/seo-spider/issues/url/multiple-slashes/index.html) Contains A Space](/content/seo-spider/issues/url/contains-a-space/index.html) Broken Bookmark](/content/seo-spider/issues/url/broken-bookmark/index.html)
Learn More About URL Warnings
Non ASCII Characters](/content/seo-spider/issues/url/non-ascii-characters/index.html) Uppercase](/content/seo-spider/issues/url/uppercase/index.html) Repetitive Path](/content/seo-spider/issues/url/repetitive-path/index.html) Internal Search](/content/seo-spider/issues/url/internal-search/index.html) Parameters](/content/seo-spider/issues/url/parameters/index.html) GA Tracking Parameters](/content/seo-spider/issues/url/ga-tracking-parameters/index.html)
Learn More About URL Opportunities
Underscores](/content/seo-spider/issues/url/underscores/index.html) Over 115 Characters](/content/seo-spider/issues/url/over-115-characters/index.html)
Page Titles
Relevant and descriptive page titles are essential, as they help both users and search engines understand the purpose of a page. Find issues related to missing, duplicate, long or even multiple page titles.
Learn More About Page Titles Issues
Missing](/content/seo-spider/issues/page-titles/page-title-missing/index.html) Multiple](/content/seo-spider/issues/page-titles/multiple/index.html) Outside
](/content/seo-spider/issues/page-titles/page-title-outside-head/index.html)Learn More About Page Titles Opportunities
Duplicate](/content/seo-spider/issues/page-titles/duplicate/index.html) Over 60 Characters](/content/seo-spider/issues/page-titles/over-60-characters/index.html) Below 30 Characters](/content/seo-spider/issues/page-titles/below-30-characters/index.html) Over 561 Pixels](/content/seo-spider/issues/page-titles/over-561-pixels/index.html) Below 200 Pixels](/content/seo-spider/issues/page-titles/below-200-pixels/index.html) Same as H1](/content/seo-spider/issues/page-titles/same-as-h1/index.html)
Meta Description
Meta descriptions can be used in search engine result snippets, so writing a good meta description can be helpful for users and drive more clicks to a website. Find issues related to missing, duplicate, long or even multiple meta descriptions.
Learn More About Meta Description Issues
Multiple](/content/seo-spider/issues/meta-description/meta-description-multiple/index.html) Outside
](/content/seo-spider/issues/meta-description/meta-description-outside-head/index.html)Learn More About Meta Description Opportunities
Missing](/content/seo-spider/issues/meta-description/meta-description-missing/index.html) Duplicate](/content/seo-spider/issues/meta-description/meta-description-duplicate/index.html) Over 155 Characters](/content/seo-spider/issues/meta-description/over-155-characters/index.html) Below 70 Characters](/content/seo-spider/issues/meta-description/below-70-characters/index.html) Over 985 Pixels](/content/seo-spider/issues/meta-description/over-985-pixels/index.html) Below 400 Pixels](/content/seo-spider/issues/meta-description/below-400-pixels/index.html)
H1
Headings help provide structure and organisation to a web page, and can allow users and search engines to better understand the content. The h1 should describe the main title and purpose of the page. Find issues related to missing, duplicate, long or non-sequential h1's.
Learn More About H1 Issues
Missing](/content/seo-spider/issues/h1/h1-missing/index.html)
Learn More About H1 Warnings
Multiple](/content/seo-spider/issues/h1/h1-multiple/index.html) Alt Text in h1](/content/seo-spider/issues/h1/alt-text-in-h1/index.html) Non-sequential](/content/seo-spider/issues/h1/h1-non-sequential/index.html)
Learn More About H1 Opportunities
Duplicate](/content/seo-spider/issues/h1/h1-duplicate/index.html) Over 70 Characters](/content/seo-spider/issues/h1/h1-over-70-characters/index.html)
H2
Headings are titles and subtitles within the copy of a page to guide users and search engines to better understand the content. The h2 heading is often used to describe sections within a document and act as signposts for the user. Find issues related to missing, duplicate, long or non-sequential h2's.
Learn More About H2 Warnings
Missing](/content/seo-spider/issues/h2/h2-missing/index.html) Multiple](/content/seo-spider/issues/h2/h2-multiple/index.html) Non-sequential](/content/seo-spider/issues/h2/h2-non-sequential/index.html)
Learn More About H2 Opportunities
Duplicate](/content/seo-spider/issues/h2/h2-duplicate/index.html) Over 70 Characters](/content/seo-spider/issues/h2/h2-over-70-characters/index.html)
Content
Ensuring your web pages deliver the best on-page content is vital to satisfy users and for SEO. Find issues related to exact and near duplicate content, low content, spelling, grammar and readability.
Learn More About Content Issues
Exact Duplicates](/content/seo-spider/issues/content/exact-duplicates/index.html) Spelling Errors](/content/seo-spider/issues/content/spelling-errors/index.html) Grammar Errors](/content/seo-spider/issues/content/grammar-errors/index.html)
Learn More About Content Warnings
Soft 404 Pages](/content/seo-spider/issues/content/soft-404-pages/index.html) Lorem Ipsum Placeholder](/content/seo-spider/issues/content/lorem-ipsum-placeholder/index.html) Near Duplicates](/content/seo-spider/issues/content/near-duplicates/index.html) Semantically Similar](/content/seo-spider/issues/content/semantically-similar/index.html) Low Relevance Content](/content/seo-spider/issues/content/low-relevance-content/index.html)
Learn More About Content Opportunities
Low Content Pages](/content/seo-spider/issues/content/low-content-pages/index.html) Readability Difficult](/content/seo-spider/issues/content/readability-difficult/index.html) Readability Very Difficult](/content/seo-spider/issues/content/readability-very-difficult/index.html)
Images
Imagery is crucial in delivering rich web experiences, whether that's to support branding, selling products or impactful visuals. Find issues related to large images, missing alt text, incorrectly sized images and cumulative layout shift.
Learn More About Images Issues
Missing Alt Text](/content/seo-spider/issues/images/missing-alt-text/index.html) Missing Alt Attribute](/content/seo-spider/issues/images/missing-alt-attribute/index.html)
Learn More About Images Warnings
Background Images](/content/seo-spider/issues/images/background-images/index.html)
Learn More About Images Opportunities
Over 100 kb](/content/seo-spider/issues/images/over-100-kb/index.html) Alt Text Over 100 Characters](/content/seo-spider/issues/images/alt-text-over-100-characters/index.html) Incorrectly Sized Images](/content/seo-spider/issues/images/incorrectly-sized-images/index.html) Missing Size Attributes](/content/seo-spider/issues/images/missing-size-attributes/index.html)
Canonicals
Rel="canonical" can be used to help reduce duplicate content, and provide a hint to the search engines about which version of a URL should be indexed in the search results. Find issues related to pages missing canonicals, canonicalised pages, non-indexable canonicals and more.
Learn More About Canonicals Issues
Multiple Conflicting](/content/seo-spider/issues/canonicals/multiple-conflicting/index.html) Non-Indexable Canonical](/content/seo-spider/issues/canonicals/non-indexable-canonical/index.html) Invalid Attribute In Annotation](/content/seo-spider/issues/canonicals/invalid-attribute-in-annotation/index.html) Contains Fragment URL](/content/seo-spider/issues/canonicals/contains-fragment-url/index.html) Outside
](/content/seo-spider/issues/canonicals/canonicals-outside-head/index.html)Learn More About Canonicals Warnings
Canonicalised](/content/seo-spider/issues/canonicals/canonicalised/index.html) Missing](/content/seo-spider/issues/canonicals/canonical-missing/index.html) Unlinked](/content/seo-spider/issues/canonicals/unlinked/index.html) Multiple](/content/seo-spider/issues/canonicals/canonical-multiple/index.html) Canonical Is Relative](/content/seo-spider/issues/canonicals/canonical-is-relative/index.html)
Pagination
Pagination is a common way to divide and display a subset of results to users for improved page performance or UX. Find issues related to pagination setup, including non-200 response URLs in pagination attributes, non-indexable paginated pages and sequence problems.
Learn More About Pagination Issues
Pagination URL Not In Anchor Tag](/content/seo-spider/issues/pagination/pagination-url-not-in-anchor-tag/index.html) Non-200 Pagination URLs](/content/seo-spider/issues/pagination/non-200-pagination-urls/index.html) Unlinked Pagination URLs](/content/seo-spider/issues/pagination/unlinked-pagination-urls/index.html) Multiple Pagination URLs](/content/seo-spider/issues/pagination/multiple-pagination-urls/index.html) Pagination Loop](/content/seo-spider/issues/pagination/pagination-loop/index.html) Sequence Error](/content/seo-spider/issues/pagination/sequence-error/index.html)
Learn More About Pagination Warnings
Non-Indexable](/content/seo-spider/issues/pagination/non-indexable/index.html)
Directives
Robots directives using either the robots meta tag or X-Robots-Tag HTTP Header give search engine crawlers instructions about how to crawl and index web pages. Find issues related to noindex, nofollow and none directives.
Learn More About Directives Issues
Outside
](/content/seo-spider/issues/directives/directive-outside-head/index.html) NoImageIndex](/content/seo-spider/issues/directives/noimageindex/index.html)Learn More About Directives Warnings
Noindex](/content/seo-spider/issues/directives/noindex/index.html) Nofollow](/content/seo-spider/issues/directives/nofollow/index.html) None](/content/seo-spider/issues/directives/none/index.html) Unavailable_After](/content/seo-spider/issues/directives/unavailable-after/index.html) NoSnippet](/content/seo-spider/issues/directives/nosnippet/index.html) NoODP](/content/seo-spider/issues/directives/noodp/index.html) NoYDIR](/content/seo-spider/issues/directives/noydir/index.html) NoTranslate](/content/seo-spider/issues/directives/notranslate/index.html)
Hreflang
Hreflang lets search engines know about multiple versions of a page for different languages and regions, to enable them to return the appropriate version to users under search. Find issues related to non-200 hreflang URLs, missing return links and incorrect language or region codes.
Learn More About Hreflang Issues
Non-200 Hreflang URLs](/content/seo-spider/issues/hreflang/non-200-hreflang-urls/index.html) Missing Return Links](/content/seo-spider/issues/hreflang/missing-return-links/index.html) Inconsistent Language & Region Confirmation Links](/content/seo-spider/issues/hreflang/inconsistent-language-region-confirmation-links/index.html) Non-Canonical Return Links](/content/seo-spider/issues/hreflang/non-canonical-return-links/index.html) Noindex Returns Links](/content/seo-spider/issues/hreflang/noindex-returns-links/index.html) Incorrect Language & Region Codes](/content/seo-spider/issues/hreflang/incorrect-language-region-codes/index.html) Multiple Entries](/content/seo-spider/issues/hreflang/multiple-entries/index.html) Not Using Canonical](/content/seo-spider/issues/hreflang/not-using-canonical/index.html) Outside
](/content/seo-spider/issues/hreflang/hreflang-outside-head/index.html) Unlinked Hreflang URLs](/content/seo-spider/issues/hreflang/unlinked-hreflang-urls/index.html)Learn More About Hreflang Warnings
Missing Self Reference](/content/seo-spider/issues/hreflang/missing-self-reference/index.html) Missing X-Default](/content/seo-spider/issues/hreflang/missing-x-default/index.html)
JavaScript
Search engines today are typically able to render web pages to crawl and index pages that use JavaScript. However, JavaScript-rich websites that rely on client-side rendering can be more fragile. Find issues related to blocked resources, identifying JS content, links and key elements.
Learn More About JavaScript Issues
Noindex Only in Original HTML](/content/seo-spider/issues/javascript/noindex-only-in-original-html/index.html) Nofollow Only in Original HTML](/content/seo-spider/issues/javascript/nofollow-only-in-original-html/index.html) Canonical Mismatch](/content/seo-spider/issues/javascript/canonical-mismatch/index.html) Uses Old AJAX Crawling Scheme URLs](/content/seo-spider/issues/javascript/uses-old-ajax-crawling-scheme-urls/index.html) Uses Old AJAX Crawling Scheme Meta Fragment Tag](/content/seo-spider/issues/javascript/uses-old-ajax-crawling-scheme-meta-fragment-tag/index.html)
Learn More About JavaScript Warnings
Pages with Blocked Resources](/content/seo-spider/issues/javascript/pages-with-blocked-resources/index.html) Contains JavaScript Links](/content/seo-spider/issues/javascript/contains-javascript-links/index.html) Contains JavaScript Content](/content/seo-spider/issues/javascript/contains-javascript-content/index.html) Page Title Only in Rendered HTML](/content/seo-spider/issues/javascript/page-title-only-in-rendered-html/index.html) Page Title Updated by JavaScript](/content/seo-spider/issues/javascript/page-title-updated-by-javascript/index.html) Meta Description Only in Rendered HTML](/content/seo-spider/issues/javascript/meta-description-only-in-rendered-html/index.html) Meta Description Updated by JavaScript](/content/seo-spider/issues/javascript/meta-description-updated-by-javascript/index.html) H1 Only in Rendered HTML](/content/seo-spider/issues/javascript/h1-only-in-rendered-html/index.html) H1 Updated by JavaScript](/content/seo-spider/issues/javascript/h1-updated-by-javascript/index.html) Canonical Only in Rendered HTML](/content/seo-spider/issues/javascript/canonical-only-in-rendered-html/index.html) Pages With JavaScript Errors](/content/seo-spider/issues/javascript/pages-with-javascript-errors/index.html)
Links
Links are used by website users to navigate pages, and by search engines to understand a website and score them. Find link issues related to pages with high crawl depth, without internal outlinks, non-descriptive anchor text and more.
Learn More About Links Issues
Outlinks To Localhost](/content/seo-spider/issues/links/outlinks-to-localhost/index.html)
Learn More About Links Warnings
Pages With Uncrawlable Internal Outlinks](/content/seo-spider/issues/links/pages-with-uncrawlable-internal-outlinks/index.html) Pages Without Internal Outlinks](/content/seo-spider/issues/links/pages-without-internal-outlinks/index.html) Non-Indexable Page Inlinks Only](/content/seo-spider/issues/links/non-indexable-page-inlinks-only/index.html) Internal Nofollow Outlinks](/content/seo-spider/issues/links/internal-nofollow-outlinks/index.html) Pages With High External Outlinks](/content/seo-spider/issues/links/pages-with-high-external-outlinks/index.html) Pages With High Internal Outlinks](/content/seo-spider/issues/links/pages-with-high-internal-outlinks/index.html) Follow & Nofollow Internal Inlinks To Page](/content/seo-spider/issues/links/follow-nofollow-internal-inlinks-to-page/index.html) Internal Nofollow Inlinks Only](/content/seo-spider/issues/links/internal-nofollow-inlinks-only/index.html)
Learn More About Links Opportunities
Pages With High Crawl Depth](/content/seo-spider/issues/links/pages-with-high-crawl-depth/index.html) Internal Outlinks With No Anchor Text](/content/seo-spider/issues/links/internal-outlinks-with-no-anchor-text/index.html) Non-Descriptive Anchor Text In Internal Outlinks](/content/seo-spider/issues/links/non-descriptive-anchor-text-in-internal-outlinks/index.html)
AMP
AMP is an open-source HTML framework that was created to help produce fast-loading pages optimised for mobile. There are specific requirements for AMP and the setup. Find issues related to the SEO setup, as well as AMP specifications using the official AMP validator.
Learn More About AMP Issues
Non-200 Response](/content/seo-spider/issues/amp/non-200-response/index.html) Missing Non-AMP Return Link](/content/seo-spider/issues/amp/missing-non-amp-return-link/index.html) Missing Canonical to Non-AMP](/content/seo-spider/issues/amp/missing-canonical-to-non-amp/index.html) Non-Indexable Canonical](/content/seo-spider/issues/amp/amp-non-indexable-canonical/index.html) Missing Tag](/content/seo-spider/issues/amp/missing-htmlamp-tag/index.html) Missing/Invalid Doctype HTML Tag](/content/seo-spider/issues/amp/missing-invalid-doctype-html-tag/index.html) Missing Head Tag](/content/seo-spider/issues/amp/amp-missing-head-tag/index.html) Missing Body Tag](/content/seo-spider/issues/amp/amp-missing-body-tag/index.html) Missing Canonical](/content/seo-spider/issues/amp/amp-missing-canonical/index.html) Missing/Invalid Meta Charset Tag](/content/seo-spider/issues/amp/missing-invalid-meta-charset-tag/index.html) Missing/Invalid Meta Viewport Tag](/content/seo-spider/issues/amp/missing-invalid-meta-viewport-tag/index.html) Missing/Invalid AMP Script](/content/seo-spider/issues/amp/missing-invalid-amp-script/index.html) Missing/Invalid AMP Boilerplate](/content/seo-spider/issues/amp/missing-invalid-amp-boilerplate/index.html) Contains Disallowed HTML](/content/seo-spider/issues/amp/contains-disallowed-html/index.html) Other Validation Errors](/content/seo-spider/issues/amp/other-validation-errors/index.html)
Learn More About AMP Warnings
Indexable](/content/seo-spider/issues/amp/indexable/index.html)
Structured Data
Structured data provides search engines with explicit clues about the meaning of pages and their components and can enable special search result features and enhancements in Google. Find issues related to Schema.org specifications and Google’s rich result feature requirements.
Learn More About Structured Data Issues
Validation Errors](/content/seo-spider/issues/structured-data/validation-errors/index.html) Rich Result Validation Errors](/content/seo-spider/issues/structured-data/rich-result-validation-errors/index.html) Parse Errors](/content/seo-spider/issues/structured-data/parse-errors/index.html)
Learn More About Structured Data Opportunities
Missing](/content/seo-spider/issues/structured-data/structured-data-missing/index.html) Validation Warnings](/content/seo-spider/issues/structured-data/validation-warnings/index.html) Rich Result Validation Warnings](/content/seo-spider/issues/structured-data/rich-result-validation-warnings/index.html)
Sitemaps
XML Sitemaps should be up to date, error free, and include indexable, canonical versions of URLs to help search engines crawl and index the URLs that are important for a website. Find issues related to URLs not in the XML Sitemap, orphan URLs and non-indexable URLs.
Learn More About Sitemaps Issues
XML Sitemap With Over 50k URLs](/content/seo-spider/issues/sitemaps/xml-sitemap-with-over-50k-urls/index.html) XML Sitemap Over 50mb](/content/seo-spider/issues/sitemaps/xml-sitemap-over-50mb/index.html) URLs Not In Sitemap](/content/seo-spider/issues/sitemaps/urls-not-in-sitemap/index.html) Orphan URLs](/content/seo-spider/issues/sitemaps/orphan-urls/index.html) Non-Indexable URLs In Sitemap](/content/seo-spider/issues/sitemaps/non-indexable-urls-in-sitemap/index.html)
Learn More About Sitemaps Warnings
URLs In Multiple Sitemaps](/content/seo-spider/issues/sitemaps/urls-in-multiple-sitemaps/index.html)
PageSpeed
Page speed is a fundamental component of UX and by integrating the PageSpeed Insights API into a crawl, speed metrics, opportunities and diagnostics can be gathered at scale. Find issues related to render-blocking resources, large images, compression and more.
Learn More About PageSpeed Opportunities
Document Request Latency](/content/seo-spider/issues/pagespeed/document-request-latency/index.html) LCP Request Discovery](/content/seo-spider/issues/pagespeed/lcp-request-discovery/index.html) Render Blocking Requests](/content/seo-spider/issues/pagespeed/eliminate-render-blocking-resources/index.html) Network Dependency Tree](/content/seo-spider/issues/pagespeed/network-dependency-tree/index.html) Use Efficient Cache Lifetimes](/content/seo-spider/issues/pagespeed/serve-static-assets-with-an-efficient-cache-policy/index.html) Layout Shift Culprits](/content/seo-spider/issues/pagespeed/avoid-large-layout-shifts/index.html) Improve Image Delivery](/content/seo-spider/issues/pagespeed/improve-image-delivery/index.html) Forced Reflow](/content/seo-spider/issues/pagespeed/forced-reflow/index.html) Legacy JavaScript](/content/seo-spider/issues/pagespeed/avoid-serving-legacy-javascript-to-modern-browsers/index.html) Duplicated JavaScript](/content/seo-spider/issues/pagespeed/duplicated-javascript/index.html) Avoid Enormous Network Payloads](/content/seo-spider/issues/pagespeed/avoid-enormous-network-payloads/index.html) Minify CSS](/content/seo-spider/issues/pagespeed/minify-css/index.html) Minify JavaScript](/content/seo-spider/issues/pagespeed/minify-javascript/index.html) Reduce Unused CSS](/content/seo-spider/issues/pagespeed/remove-unused-css/index.html) Reduce Unused JavaScript](/content/seo-spider/issues/pagespeed/remove-unused-javascript/index.html) Reduce JavaScript Execution Time](/content/seo-spider/issues/pagespeed/reduce-javascript-execution-time/index.html) Minimize Main-Thread Work](/content/seo-spider/issues/pagespeed/minimize-main-thread-work/index.html) Optimize DOM Size](/content/seo-spider/issues/pagespeed/avoid-excessive-dom-size/index.html) Font Display](/content/seo-spider/issues/pagespeed/ensure-text-remains-visible-during-webfont-load/index.html)
Mobile
Websites must provide friendly and rich experience on mobile devices, as well as desktop. Test web pages using Lighthouse to identify mobile usability issues related to viewport, tap targets, content sizing and more.
Learn More About Mobile Issues
Viewport Not Set](/content/seo-spider/issues/mobile/viewport-not-set/index.html) Content Not Sized Correctly](/content/seo-spider/issues/mobile/content-not-sized-correctly/index.html) Illegible Font Size](/content/seo-spider/issues/mobile/illegible-font-size/index.html) Contains Unsupported Plugins](/content/seo-spider/issues/mobile/contains-unsupported-plugins/index.html) Target Size](/content/seo-spider/issues/mobile/target-size/index.html)
Learn More About Mobile Warnings
Mobile Alternate Link](/content/seo-spider/issues/mobile/mobile-alternate-link/index.html)
Accessibility
Improve site accessibility to make them more inclusive and user friendly for people with disabilities. Automate finding accessibility issues using the inbuilt open-source AXE accessibility engine that powers Lighthouse.
Learn More About Accessibility Warnings
Best Practice – Accesskey Attribute Value Must Be Unique](/content/seo-spider/issues/accessibility/best-practice-accesskey-attribute-value-must-be-unique/index.html) Best Practice – Elements Must Not Have Tabindex Greater Than Zero](/content/seo-spider/issues/accessibility/best-practice-elements-must-not-have-tabindex-greater-than-zero/index.html) Best Practice – ARIA Dialog & Alertdialog Require Accessible Name](/content/seo-spider/issues/accessibility/best-practice-aria-dialog-alertdialog-require-accessible-name/index.html) Best Practice – ARIA Treeitem Nodes Require Accessible Name](/content/seo-spider/issues/accessibility/best-practice-aria-treeitem-nodes-require-accessible-name/index.html) Best Practice – Role=text Should Have No Focusable Descendants](/content/seo-spider/issues/accessibility/best-practice-roletext-should-have-no-focusable-descendants/index.html) Best Practice – Form Elements Should Have Visible Label](/content/seo-spider/issues/accessibility/best-practice-form-elements-should-have-visible-label/index.html) Best Practice – Frames Should Be Tested With axe-core](/content/seo-spider/issues/accessibility/best-practice-frames-should-be-tested-with-axe-core/index.html) Best Practice – Scope Attribute Should Be Used Correctly On Tables](/content/seo-spider/issues/accessibility/best-practice-scope-attribute-should-be-used-correctly-on-tables/index.html) WCAG 2.0 A – Scrollable Region Requires Keyboard Access](/content/seo-spider/issues/accessibility/wcag-2-0-a-scrollable-region-requires-keyboard-access/index.html) WCAG 2.0 A – Required ARIA Attributes Must Be Provided](/content/seo-spider/issues/accessibility/wcag-2-0-a-required-aria-attributes-must-be-provided/index.html) WCAG 2.0 A – ARIA Attribute Must Be Used As Specified For Role](/content/seo-spider/issues/accessibility/wcag-2-0-a-aria-attribute-must-be-used-as-specified-for-role/index.html) WCAG 2.0 A – ARIA Attributes Require Valid Values](/content/seo-spider/issues/accessibility/wcag-2-0-a-aria-attributes-require-valid-values/index.html) WCAG 2.0 A – ARIA Attributes Require Valid Names](/content/seo-spider/issues/accessibility/wcag-2-0-a-aria-attributes-require-valid-names/index.html) WCAG 2.0 A – ARIA Commands Require Accessible Name](/content/seo-spider/issues/accessibility/wcag-2-0-a-aria-commands-require-accessible-name/index.html) WCAG 2.0 A – ARIA Input Fields Require Accessible Name](/content/seo-spider/issues/accessibility/wcag-2-0-a-aria-input-fields-require-accessible-name/index.html) WCAG 2.0 A – ARIA Meter Nodes Require Accessible Name](/content/seo-spider/issues/accessibility/wcag-2-0-a-aria-meter-nodes-require-accessible-name/index.html) WCAG 2.0 A – ARIA Progressbar Nodes Require Accessible Name](/content/seo-spider/issues/accessibility/wcag-2-0-a-aria-progressbar-nodes-require-accessible-name/index.html) WCAG 2.0 A – ARIA Roles Must Be Contained By Required Parent](/content/seo-spider/issues/accessibility/wcag-2-0-a-aria-roles-must-be-contained-by-required-parent/index.html) WCAG 2.0 A – ARIA Roles Require Valid Values](/content/seo-spider/issues/accessibility/wcag-2-0-a-aria-roles-require-valid-values/index.html) WCAG 2.0 A – ARIA Toggle Fields Require Accessible Name](/content/seo-spider/issues/accessibility/wcag-2-0-a-aria-toggle-fields-require-accessible-name/index.html) WCAG 2.0 A – ARIA Tooltip Nodes Require Accessible Name](/content/seo-spider/issues/accessibility/wcag-2-0-a-aria-tooltip-nodes-require-accessible-name/index.html) WCAG 2.0 A – Certain ARIA Roles Must Contain Specific Children](/content/seo-spider/issues/accessibility/wcag-2-0-a-certain-aria-roles-must-contain-specific-children/index.html) WCAG 2.0 A – Aria-braille Require Non-braille Equivalent](/content/seo-spider/issues/accessibility/wcag-2-0-a-aria-braille-require-non-braille-equivalent/index.html) WCAG 2.0 A – Aria-hidden Elements Contains Focusable Elements](/content/seo-spider/issues/accessibility/wcag-2-0-a-aria-hidden-elements-contains-focusable-elements/index.html) WCAG 2.0 A – Aria-hidden=true Must Not Be Used In
](/content/seo-spider/issues/accessibility/wcag-2-0-a-aria-hiddentrue-must-not-be-used-in-body/index.html) WCAG 2.0 A – Elements Must Only Use Permitted ARIA Attributes](/content/seo-spider/issues/accessibility/wcag-2-0-a-elements-must-only-use-permitted-aria-attributes/index.html) WCAG 2.0 A – Elements Must Use Allowed ARIA Attributes](/content/seo-spider/issues/accessibility/wcag-2-0-a-elements-must-use-allowed-aria-attributes/index.html) WCAG 2.0 A – IDs Used In ARIA & Labels Must Be Unique](/content/seo-spider/issues/accessibility/wcag-2-0-a-ids-used-in-aria-labels-must-be-unique/index.html) WCAG 2.0 A – Page Requires Means To Bypass Repeated Blocks](/content/seo-spider/issues/accessibility/wcag-2-0-a-page-requires-means-to-bypass-repeated-blocks/index.html) WCAG 2.0 A – Form Elements Require Labels](/content/seo-spider/issues/accessibility/wcag-2-0-a-form-input-elements-require-labels/index.html) WCAG 2.0 A – Frames Require Title Attribute](/content/seo-spider/issues/accessibility/wcag-2-0-a-frames-require-title-attribute/index.html) WCAG 2.0 A – Frames Require Unique Title Attribute](/content/seo-spider/issues/accessibility/wcag-2-0-a-frames-require-unique-title-attribute/index.html) WCAG 2.0 A – Frames With Focusable Content Must Not Use tabindex=-1](/content/seo-spider/issues/accessibility/wcag-2-0-a-frames-with-focusable-content-must-not-use-tabindex-1/index.html) WCAG 2.0 A – Page Must Contain