- Response Codes
- Internal No Response
- Internal Client Error (4XX)
- Internal Server Error (5XX)
- Internal Redirect Loop
- Internal Blocked by Robots.txt
- Internal Blocked Resource
- Internal Redirect Chain
- External Blocked Resource
- Internal Redirection (3XX)
- Internal Redirection (Meta Refresh)
- Internal Redirection (JavaScript)
- External No Response
- External Client Error (4XX)
- External Server Error (5XX)
- Security
- HTTP URLs
- Mixed Content
- Form URL Insecure
- Form On HTTP URL
- Missing HSTS Header
- Unsafe Cross Origin Links
- Protocol-Relative Resource Links
- Missing Content-Security-Policy Header
- Missing X-Content-Type-Options Header
- Missing X-Frames-Options Header
- Missing Secure Referrer-Policy Header
- Bad Content Type
- Hreflang
- Non-200 Hreflang URLs
- Missing Return Links
- Inconsistent Language & Region Confirmation Links
- Non-Canonical Return Links
- Noindex Returns Links
- Incorrect Language & Region Codes
- Multiple Entries
- Not Using Canonical
- Outside <head>
- Unlinked Hreflang URLs
- Missing Self Reference
- Missing X-Default
- JavaScript
- Noindex Only in Original HTML
- Nofollow Only in Original HTML
- Canonical Mismatch
- Uses Old AJAX Crawling Scheme URLs
- Uses Old AJAX Crawling Scheme Meta Fragment Tag
- Pages with Blocked Resources
- Contains JavaScript Links
- Contains JavaScript Content
- Page Title Only in Rendered HTML
- Page Title Updated by JavaScript
- Meta Description Only in Rendered HTML
- Meta Description Updated by JavaScript
- H1 Only in Rendered HTML
- H1 Updated by JavaScript
- Canonical Only in Rendered HTML
- Pages With JavaScript Errors
- Links
- Outlinks To Localhost
- Pages Without Internal Outlinks
- Non-Indexable Page Inlinks Only
- Internal Nofollow Outlinks
- Pages With High External Outlinks
- Pages With High Internal Outlinks
- Follow & Nofollow Internal Inlinks To Page
- Internal Nofollow Inlinks Only
- Pages With High Crawl Depth
- Internal Outlinks With No Anchor Text
- Non-Descriptive Anchor Text In Internal Outlinks
- AMP
- Non-200 Response
- Missing Non-AMP Return Link
- Missing Canonical to Non-AMP
- Non-Indexable Canonical
- Missing <html amp> Tag
- Missing/Invalid Doctype HTML Tag
- Missing Head Tag
- Missing Body Tag
- Missing Canonical
- Missing/Invalid Meta Charset Tag
- Missing/Invalid Meta Viewport Tag
- Missing/Invalid AMP Script
- Missing/Invalid AMP Boilerplate
- Contains Disallowed HTML
- Other Validation Errors
- Indexable
- Structured Data
- Validation Errors
- Missing
- Validation Warnings
- PageSpeed
- Eliminate Render-Blocking Resources
- Properly Size Images
- Defer Offscreen Images
- Minify CSS
- Minify JavaScript
- Reduce Unused CSS
- Reduce Unused JavaScript
- Efficiently Encode Images
- Serve Images in Next-Gen Formats
- Enable Text Compression
- Preconnect to Required Origin
- Reduce Server Response Times (TTFB)
- Preload Key Requests
- Reduce JavaScript Execution Time
- Serve Static Assets With An Efficient Cache Policy
- Minimize Main-Thread Work
- Image Elements Do Not Have Explicit Width & Height
- Avoid Large Layout Shifts
- Avoid Serving Legacy JavaScript to Modern Browsers
- Avoid Multiple Page Redirects
- Use Video Format for Animated Images
- Avoid Excessive DOM Size
- Ensure Text Remains Visible During Webfont Load
Missing Non-AMP Return Link
AMP URLs that have a canonical non-AMP version that does not contain a rel=”amphtml” URL back to the AMP URL.
This could simply be missing from the non-AMP version, or there might be a configuration issue with the AMP canonical.
How to Analyse in the SEO Spider
View URLs with this issue in the ‘AMP’ tab and ‘Missing Non-AMP Return Link’ filter, and export all URLs using the ‘Export’ button.
The ‘Canonical Link Element’ column shows the non-AMP version that is missing the rel=”amphtml” back to the AMP URL.
Read our tutorial on ‘How To Audit & Validate Accelerated Mobile Pages (AMP)‘.
What Triggers This Issue
This issue is triggered when AMP URLs are associated with a canonical non-AMP version that lacks a rel=”amphtml” link pointing back to the AMP URL.
For example:
https://www.screamingfrog.co.uk/amp/technical-seo/
References its non-AMP counterpart with the below canonical link element:
<link rel="canonical" href="https://www.screamingfrog.co.uk/technical-seo/">
But the canonicalised URL does not point back with the below ‘amphtml’:
<link rel="amphtml" href="https://www.screamingfrog.co.uk/amp/technical-seo/">
How To Fix
Ensure canonical and non-AMP versions of URLs contain a rel=”amphtml” link to the AMP version so they are discoverable and confirm the relationship.
Further Reading
- How To Audit & Validate Accelerated Mobile Pages (AMP) - From Screaming Frog
- Validate AMP content for Google Search - From Google