Checks reference (146)

Severity says how confident we are that this hurts; priority says how soon to act. Every check here has a matching filter in the app and a regression fixture in our test suite.

Response Codes · URL · Page Titles · Meta Description · Meta Keywords · H1 · H2 · Content · Content rules · Images · Canonicals · Pagination · Directives · Hreflang · JavaScript · Links · Security · Structured Data · Sitemaps · Validation · Crawl

Response Codes

Severity	Priority	Check	What it means and how to fix it
error	high	No response `rc_no_response`	The server did not respond (DNS failure, connection refused, reset, or timeout). Fix: Check the host resolves, the server is up, and it responds within the timeout. Retry the crawl for intermittent issues.
error	high	Timed out `rc_timeout`	The request exceeded the configured timeout. Fix: Investigate server response times for the URL. Raise the timeout only if the server is legitimately slow.
error	high	Internal client error (4xx) `rc_client_error_4xx`	An internal URL returns a 4xx such as 404 or 410. Links to it are broken for users and waste crawl budget. Fix: Fix or remove the linking pages (see Inlinks), or redirect the URL to the best replacement.
error	high	Internal server error (5xx) `rc_server_error_5xx`	An internal URL returns a 5xx error. Fix: Check server logs for the URL. Persistent 5xx responses lead to de-indexing.
error	high	Redirect loop `rc_redirect_loop`	The redirect chain returns to a URL already visited, so it never resolves. Fix: Fix the redirect rules so the chain ends on a 200 page.
error	high	Redirect to error page `rc_redirect_to_error`	The URL redirects to a page that returns 4xx or 5xx. Fix: Redirect to a live page instead.
warning	medium	Blocked by robots.txt `rc_blocked_by_robots`	Internal URL disallowed by robots.txt, so it was not fetched. Fix: Confirm the block is intended. Pages blocked here cannot be crawled or indexed via the link graph; remove the disallow rule if the page should rank.
warning	high	Blocked resource `rc_blocked_resource`	A CSS, JavaScript or image file is blocked by robots.txt. Google renders pages with these resources, so blocking them can hide content and layout from indexing. Fix: Allow Googlebot to fetch CSS, JS and images used for rendering.
warning	low	Internal redirection (3xx) `rc_redirect_3xx`	Internal URL responds with a redirect. Linking straight to the final URL saves a hop for users and crawlers. Fix: Update internal links to point at the redirect target.
warning	low	Temporary redirect (302/307) `rc_redirect_302`	A temporary redirect may keep the old URL indexed. Use 301/308 for permanent moves. Fix: Change to a 301 or 308 if the move is permanent.
warning	medium	Meta refresh redirect `rc_meta_refresh`	The page redirects via <meta http-equiv="refresh">. Slower than an HTTP redirect and weaker as a signal. Fix: Replace with a server-side 301 redirect.
warning	medium	JavaScript redirect `rc_js_redirect`	The rendered page ended on a different URL than requested, so JavaScript redirected it. Fix: Use an HTTP 301 redirect instead of a client-side redirect.
warning	medium	External client error (4xx) `rc_external_client_error`	An external link target returns 4xx. Fix: Update or remove the outbound link (see Inlinks for where it appears).
warning	low	External server error (5xx) `rc_external_server_error`	An external link target returns 5xx. Fix: Re-check later; remove the link if it stays down.
warning	low	External no response `rc_external_no_response`	An external link target did not respond. Fix: Re-check later; remove the link if it stays down.
warning	medium	Redirect chain `rc_redirect_chain`	The URL redirects to another URL that also redirects. Each hop adds latency and loses signals. Fix: Point the first URL straight at the final destination.
warning	low	Slow response (>1s) `rc_slow_response`	Time to download the HTML exceeded one second. Fix: Improve server response time: caching, faster hosting, fewer blocking queries.

URL

Severity	Priority	Check	What it means and how to fix it
warning	low	Non-ASCII characters `url_non_ascii`	URL contains characters outside ASCII. Fix: Prefer ASCII, lowercase, hyphen-separated slugs.
warning	low	Uppercase characters `url_uppercase`	URL path contains uppercase characters, which can create duplicate variants. Fix: Serve lowercase URLs and redirect uppercase variants.
warning	low	Repetitive path `url_repetitive_path`	The same path segment repeats, often a sign of a relative-link bug creating infinite URLs. Fix: Fix the relative link that generates the repeated segment.
warning	low	Multiple slashes `url_multiple_slashes`	The path contains "//". Fix: Normalise and redirect to the single-slash version.
warning	low	Contains space `url_space`	URL contains a space or %20. Fix: Use hyphens instead of spaces.
warning	medium	Session ID in URL `url_session_id`	URL carries a session identifier, which creates unlimited duplicates. Fix: Keep sessions in cookies; canonicalise the URL.
opportunity	low	Underscores `url_underscores`	URL path uses underscores. Google treats hyphens as word separators, underscores not reliably. Fix: Use hyphens in new URLs; do not rename existing ranking URLs just for this.
opportunity	low	Parameters `url_parameters`	URL includes query parameters, which often create duplicates. Fix: Confirm parameterised URLs are canonicalised or blocked where appropriate.
opportunity	low	Over 115 characters `url_over_115`	Very long URL. Fix: Keep URLs short and descriptive.

Page Titles

Severity	Priority	Check	What it means and how to fix it
error	high	Missing title `title_missing`	The page has no <title>. Titles are a primary ranking and click-through signal. Fix: Add a unique, descriptive <title> inside <head>.
warning	medium	Duplicate title `title_duplicate`	Another page uses the same title. Fix: Give each page a unique title that describes its content.
warning	low	Over 60 characters `title_over_60`	Title is longer than 60 characters and may be truncated in results. Fix: Shorten the title, front-loading the key terms.
warning	low	Over 580 pixels `title_over_px`	Title is wider than Google typically displays (~580px). Fix: Shorten the title.
warning	medium	Multiple titles `title_multiple`	More than one <title> element found. Fix: Keep a single <title> in <head>.
warning	medium	Title outside head `title_outside_head`	The <title> appears after an element that closed <head> early, so it may be ignored. Fix: Move the title into <head> and remove invalid elements before it.
opportunity	low	Under 30 characters `title_under_30`	Short titles may miss relevant terms. Fix: Expand the title with descriptive terms.
opportunity	low	Same as H1 `title_same_as_h1`	Title and H1 are identical. Not an error, but an opportunity to target variations. Fix: Consider a different but consistent title and H1.

Meta Description

Severity	Priority	Check	What it means and how to fix it
warning	medium	Missing meta description `desc_missing`	No meta description. Google may write its own snippet. Fix: Add a unique description of 70 to 155 characters.
warning	medium	Duplicate meta description `desc_duplicate`	Another page has the same meta description. Fix: Write a unique description per page.
warning	low	Over 155 characters `desc_over_155`	The description is likely to be truncated. Fix: Shorten to under 155 characters.
warning	low	Over 990 pixels `desc_over_px`	The description is wider than typically displayed. Fix: Shorten the description.
warning	medium	Multiple meta descriptions `desc_multiple`	More than one meta description found. Fix: Keep one.
opportunity	low	Under 70 characters `desc_under_70`	Short description leaves snippet space unused. Fix: Expand with a useful summary and call to action.

Meta Keywords

Severity	Priority	Check	What it means and how to fix it
info	low	Meta keywords present `mk_present`	Meta keywords are ignored by Google and reveal targeting to competitors. Fix: Remove the tag unless another engine you care about uses it.

H1

Severity	Priority	Check	What it means and how to fix it
warning	medium	Missing H1 `h1_missing`	No H1 heading on the page. Fix: Add a single descriptive H1.
warning	low	Duplicate H1 `h1_duplicate`	Another page uses the same H1. Fix: Make each H1 unique.
warning	low	H1 over 70 characters `h1_over_70`	The H1 is long. Fix: Shorten the H1.
warning	low	Multiple H1 `h1_multiple`	More than one H1 on the page. Fix: Keep one H1; demote others to H2.

H2

Severity	Priority	Check	What it means and how to fix it
opportunity	low	Missing H2 `h2_missing`	No H2 headings. Subheadings help structure and comprehension. Fix: Break content into sections with H2s.
opportunity	low	Duplicate H2 `h2_duplicate`	Another page uses the same first H2. Fix: Vary subheadings per page where sensible.
opportunity	low	H2 over 70 characters `h2_over_70`	The first H2 is long. Fix: Shorten the H2.
opportunity	low	H2 before H1 `h2_non_sequential`	Heading levels are out of order. Fix: Order headings H1, then H2, then H3.

Content

Severity	Priority	Check	What it means and how to fix it
warning	high	Exact duplicate `content_exact_duplicate`	Visible text is identical to another page. Fix: Canonicalise, redirect or differentiate the duplicates.
warning	medium	Near duplicate (≥90%) `content_near_duplicate`	Visible text is at least 90% similar to another page. Fix: Consolidate or differentiate the pages.
warning	high	Soft 404 `content_soft_404`	Returns 200 but looks like a not-found page. Fix: Return a real 404/410 status, or restore the content.
warning	high	Lorem ipsum placeholder `content_lorem_ipsum`	Placeholder text found. Fix: Replace with real copy or noindex the page.
warning	high	Mojibake (broken encoding) `content_mojibake`	Characters like â€™ or Ã© indicate UTF-8 shown as Latin-1. Fix: Fix the stored text or the declared charset.
opportunity	low	Low content (<200 words) `content_low_word_count`	Thin page with fewer than 200 words of visible text. Fix: Expand the content or merge the page into a stronger one.
opportunity	low	Readability: difficult `content_readability_difficult`	Flesch reading ease under 30 (college-level English). Fix: Shorter sentences and simpler words, if the audience calls for it.

Content rules

Severity	Priority	Check	What it means and how to fix it
warning	high	Banned phrase `content_banned_phrase`	A phrase from your content rules appears on the page. Fix: Rewrite the sentence per your messaging rules.

Images

Severity	Priority	Check	What it means and how to fix it
error	high	Broken image `img_broken`	The image URL returns an error. Fix: Fix the src or restore the file.
warning	medium	Missing alt attribute `img_missing_alt`	An <img> has no alt attribute. Fix: Add alt text, or alt="" for purely decorative images.
warning	low	Missing width/height `img_missing_size_attrs`	Images without size attributes cause layout shift (CLS). Fix: Add width and height attributes.
opportunity	low	Empty alt text `img_alt_empty`	An <img> has alt="". Fine for decorative images, missed opportunity otherwise. Fix: Describe meaningful images.
opportunity	low	Alt text over 100 characters `img_alt_over_100`	Very long alt text. Fix: Keep alt text concise.
opportunity	low	Image over 100 KB `img_over_100kb`	Large image file. Fix: Compress, resize or serve WebP/AVIF.

Canonicals

Severity	Priority	Check	What it means and how to fix it
error	high	Conflicting canonicals `canonical_conflict`	Multiple canonicals point at different URLs; Google ignores all of them. Fix: Keep one canonical.
error	high	Canonical to non-indexable URL `canonical_non_indexable`	The canonical target redirects, errors or is noindex. Fix: Point the canonical at a 200, indexable URL.
warning	medium	Multiple canonicals `canonical_multiple`	More than one canonical declared (HTML or HTTP header). Fix: Keep a single canonical.
warning	medium	Relative canonical `canonical_relative`	Canonical href is relative. Absolute URLs avoid ambiguity. Fix: Use the absolute URL.
warning	medium	Canonical target not linked `canonical_unlinked`	The canonical target has no internal links. Fix: Link to the canonical URL internally.
warning	medium	Canonical protocol mismatch `canonical_protocol_mismatch`	HTTPS page canonicalises to HTTP or vice versa. Fix: Canonicalise to the HTTPS URL.
warning	medium	Noindex with canonical `canonical_noindex_conflict`	The page is noindex but declares a canonical to another URL. Mixed signals. Fix: Use one or the other.
opportunity	low	Missing canonical `canonical_missing`	No canonical link. Self-referencing canonicals protect against parameter duplicates. Fix: Add <link rel="canonical"> pointing at the preferred URL.
info	low	Canonicalised `canonicalised`	The canonical points at a different URL, so this page is not meant to be indexed. Fix: Confirm the canonical target is correct.

Pagination

Severity	Priority	Check	What it means and how to fix it
warning	medium	Pagination target not indexable `pagination_non_indexable_target`	rel=next/prev points at a URL that is not 200 and indexable. Fix: Fix the pagination target.

Directives

Severity	Priority	Check	What it means and how to fix it
warning	medium	Nofollow `dir_nofollow`	Meta robots nofollow stops link equity flowing from this page. Fix: Remove nofollow unless intended.
warning	high	Robots "none" `dir_none`	robots "none" = noindex, nofollow. Fix: Confirm it is intended.
warning	low	Multiple robots meta tags `dir_multiple_robots`	More than one robots meta tag. Fix: Merge into one tag.
info	low	Noindex `dir_noindex`	Page carries noindex (meta or X-Robots-Tag). Fix: Confirm it should be excluded from search.
info	low	Noarchive / nosnippet / noimageindex `dir_noarchive`	Restrictive snippet directives present. Fix: Confirm they are intended.
info	low	Unavailable_after `dir_unavailable_after`	Page sets an expiry for indexing. Fix: Confirm the date.

Hreflang

Severity	Priority	Check	What it means and how to fix it
error	high	Missing return links `hl_missing_return_links`	A page this URL references via hreflang does not reference it back; Google ignores one-way hreflang. Fix: Add reciprocal hreflang annotations.
error	high	Hreflang to non-200 URL `hl_non_200`	An hreflang target redirects or errors. Fix: Point hreflang at final 200 URLs.
error	high	Invalid language code `hl_invalid_code`	hreflang value is not a valid ISO 639-1 language (optionally with ISO 3166-1 region). Fix: Use codes like en, en-GB, de-AT.
warning	medium	Missing self reference `hl_missing_self`	The page does not include itself in its hreflang set. Fix: Add a self-referencing hreflang.
warning	medium	Hreflang to non-canonical URL `hl_noncanonical`	An hreflang target canonicalises elsewhere. Fix: Point hreflang at canonical URLs.
warning	medium	Hreflang to noindex URL `hl_noindex_target`	An hreflang target is noindex. Fix: Remove it from the set or make it indexable.
warning	medium	Multiple entries for one language `hl_multiple_same_lang`	The same language code points at different URLs. Fix: Keep one URL per language-region.
warning	medium	Inconsistent language confirmation `hl_inconsistent_lang`	The hreflang target declares itself (html lang) as a different language. Fix: Align hreflang and html lang.
opportunity	low	Missing x-default `hl_missing_x_default`	No x-default alternate. Fix: Add x-default for unmatched languages.

JavaScript

Severity	Priority	Check	What it means and how to fix it
warning	high	Noindex only in rendered HTML `js_noindex_only_rendered`	JavaScript injects noindex. Google may index the page before rendering it. Fix: Put noindex in the raw HTML or HTTP header.
warning	medium	Canonical only in rendered HTML `js_canonical_only_rendered`	Canonical is added by JavaScript. Fix: Put the canonical in the raw HTML.
warning	high	Canonical mismatch raw vs rendered `js_canonical_mismatch`	JavaScript changes the canonical URL. Fix: Make raw and rendered canonicals agree.
warning	low	Title updated by JavaScript `js_title_updated`	The rendered title differs from the raw HTML title. Fix: Server-render the final title.
warning	low	Meta description updated by JavaScript `js_desc_updated`	The rendered description differs from the raw one. Fix: Server-render the description.
warning	low	H1 updated by JavaScript `js_h1_updated`	The rendered H1 differs from the raw one. Fix: Server-render the H1.
warning	medium	Render timed out `js_render_timeout`	Network never went idle within the render timeout; captured DOM may be incomplete. Fix: Reduce long-polling/analytics noise or raise the render timeout.
info	low	Content only in rendered HTML `js_content_only_rendered`	Rendered word count is substantially higher than raw. Content depends on JavaScript. Fix: Server-side render or pre-render key content.
info	low	Links only in rendered HTML `js_links_only_rendered`	Internal links exist only after JavaScript runs. Fix: Output primary navigation in raw HTML.
info	low	JavaScript errors `js_console_errors`	Page errors were logged during rendering. Fix: Fix the script errors.
info	low	Failed resource requests during render `js_failed_requests`	Some resources failed to load while rendering. Fix: Check the failing URLs.

Links

Severity	Priority	Check	What it means and how to fix it
error	high	Links to localhost or staging `links_to_localhost`	Links point at localhost, 127.0.0.1 or a dev host. Fix: Fix the hrefs.
warning	low	Crawl depth over 3 `links_high_crawl_depth`	Page is 4 or more clicks from the start page. Fix: Add internal links from shallower pages.
warning	low	Internal outlinks with no anchor text `links_no_anchor_text`	Some internal links have no anchor text, alt or aria-label. Fix: Add descriptive anchor text.
warning	low	Internal nofollow outlinks `links_internal_nofollow`	Internal links marked nofollow. Fix: Remove nofollow from internal links.
warning	medium	No internal outlinks `links_no_internal_outlinks`	The page links to no other internal page (dead end). Fix: Add navigation or contextual links.
warning	high	Orphan URL `links_orphan`	Found in a sitemap but with no internal inlinks. Fix: Link to the page from relevant pages, or remove it from the sitemap.
warning	medium	Only nofollow inlinks `links_only_nofollow_inlinks`	Every internal link to this page is nofollow. Fix: Add at least one followed link.
warning	low	Internal links to redirect `links_to_redirect`	Internal pages link to this redirecting URL. Fix: Update the links to the final URL (see Inlinks).
opportunity	low	Non-descriptive anchor text `links_non_descriptive_anchor`	Anchors such as "click here" or "read more". Fix: Use anchors that describe the target.
opportunity	low	Over 100 external outlinks `links_high_external_outlinks`	Many outbound links. Fix: Review for link quality.
opportunity	low	Over 500 internal outlinks `links_high_internal_outlinks`	Very many internal links dilute each link. Fix: Trim navigation or paginate.
opportunity	low	Only one inlink `links_single_inlink`	The page has a single internal inlink. Fix: Add more internal links to important pages.

Security

Severity	Priority	Check	What it means and how to fix it
error	high	Mixed content `sec_mixed_content`	HTTPS page loads HTTP resources, which browsers block or flag. Fix: Load all resources over HTTPS.
error	high	Form posts to HTTP `sec_insecure_form_action`	Form action uses http://. Fix: Post to HTTPS.
warning	low	Unsafe cross-origin links `links_unsafe_cross_origin`	target="_blank" links without rel="noopener". Fix: Add rel="noopener" (modern browsers default it, legacy ones do not).
warning	high	HTTP URL `sec_http_url`	Internal page served over HTTP. Fix: Serve over HTTPS and redirect HTTP.
warning	medium	Form on HTTP page `sec_form_on_http`	A form on an insecure page. Fix: Serve the page over HTTPS.
warning	low	Missing HSTS header `sec_missing_hsts`	No Strict-Transport-Security header. Fix: Add HSTS once HTTPS is stable.
warning	low	Missing X-Content-Type-Options `sec_missing_xcto`	No X-Content-Type-Options: nosniff. Fix: Add the header.
warning	low	Missing X-Frame-Options / frame-ancestors `sec_missing_xfo`	Page can be framed by any site (clickjacking). Fix: Add X-Frame-Options or CSP frame-ancestors.
warning	low	Missing secure Referrer-Policy `sec_missing_referrer_policy`	No Referrer-Policy header. Fix: Add Referrer-Policy: strict-origin-when-cross-origin.
warning	low	Protocol-relative resource links `sec_protocol_relative`	Resources referenced with "//host/path". Fix: Use https:// explicitly.
warning	low	Missing or wrong Content-Type `sec_bad_content_type`	The response has no Content-Type, or an HTML page is not served as text/html. Fix: Set the correct Content-Type header.
opportunity	low	Missing Content-Security-Policy `sec_missing_csp`	No CSP header. Fix: Add a CSP that fits your scripts.

Structured Data

Severity	Priority	Check	What it means and how to fix it
error	high	Structured data parse error `sd_parse_error`	JSON-LD could not be parsed. Fix: Fix the JSON syntax.
error	high	Structured data missing required property `sd_validation_error`	A rich result type lacks a required property, so Google will not show the rich result. Fix: Add the missing property.
warning	low	Structured data missing recommended property `sd_validation_warning`	A recommended property is missing. Fix: Add it where you have the data.
info	low	Mixed formats `sd_microdata_and_jsonld`	Both microdata and JSON-LD present. Fix: Prefer JSON-LD only, to avoid conflicting values.

Sitemaps

Severity	Priority	Check	What it means and how to fix it
error	high	Non-200 URL in sitemap `sm_non_200_in_sitemap`	A sitemap URL redirects or errors. Fix: List only final, live URLs.
warning	medium	Noindex URL in sitemap `sm_noindex_in_sitemap`	A noindex page is listed in an XML sitemap. Fix: Remove it from the sitemap.
warning	medium	Canonicalised URL in sitemap `sm_canonicalised_in_sitemap`	A sitemap URL canonicalises to another URL. Fix: List the canonical URL instead.
warning	medium	No XML sitemap found `sm_sitemap_missing`	No sitemap in robots.txt or at /sitemap.xml. Fix: Publish a sitemap and reference it in robots.txt.
warning	medium	Sitemap could not be fetched or parsed `sm_sitemap_error`	A referenced sitemap returned an error or was invalid. Fix: Fix the sitemap URL or XML.
warning	medium	Sitemap URL on another host `sm_foreign_url_in_sitemap`	A sitemap lists URLs outside the crawled host. Fix: Sitemaps may only list URLs on their own host.
opportunity	low	Indexable URL not in sitemap `sm_not_in_sitemap`	An indexable page is missing from the sitemaps. Fix: Add it to a sitemap.

Validation

Severity	Priority	Check	What it means and how to fix it
error	high	HTML over 15 MB `val_html_over_15mb`	Googlebot stops reading HTML after 15 MB. Fix: Reduce page size.
error	high	Missing head `val_missing_head`	No <head> element. Fix: Add a head with title and meta tags.
warning	low	Missing doctype `val_missing_doctype`	No <!DOCTYPE html>, so browsers use quirks mode. Fix: Add the doctype as the first line.
warning	low	Charset declared after 1024 bytes `val_charset_after_1024`	The charset meta appears late in <head>. Fix: Declare charset in the first 1024 bytes.
warning	medium	Missing viewport meta `val_missing_viewport`	No viewport meta, so the page is not mobile friendly. Fix: Add <meta name="viewport" content="width=device-width, initial-scale=1">.
warning	medium	Invalid element in head `val_invalid_head_element`	A body element (div, img, p, iframe...) appears inside <head>, which closes head early and can hide meta tags from Google. Fix: Move the element into <body>.
warning	low	Missing html lang `val_missing_lang`	The <html> element has no lang attribute. Fix: Add lang="en" (or the page language).
warning	medium	Multiple head or body `val_multiple_head`	More than one <head> or <body>. Fix: Keep one of each.

Crawl

Severity	Priority	Check	What it means and how to fix it
error	high	robots.txt server error `crawl_robots_5xx`	robots.txt returned 5xx. Google treats this as "crawl nothing". Fix: Make robots.txt return 200 or 404.
error	high	Rate limited (429 / 1015) `crawl_rate_limited`	The server or CDN throttled the crawler. Data for this URL is not trustworthy. Fix: Lower concurrency, add a delay, or allowlist the crawler user agent.
info	low	robots.txt missing `crawl_robots_missing`	No robots.txt (404). Everything is crawlable, but you cannot declare sitemaps. Fix: Publish a robots.txt.
info	low	Crawl limit reached `crawl_too_many_urls`	The crawl stopped at the configured URL limit. Fix: Raise the limit for a complete audit.