Alt attributes provide a text alternative for images, used by screen readers when a user cannot see the image and by search engines and multimodal AI models to understand what the image depicts. Fixing this issue means writing concise, descriptive alt text for every meaningful image on the page, and using empty alt for purely decorative images so assistive technology can skip them. The same alt text helps multimodal LLMs and image search tools surface and cite your visuals.

Example

<img src="/images/marathon-shoes.jpg"
     alt="Side view of a lightweight neon-green marathon running shoe">

<img src="/images/divider.svg" alt="">

Where to make the change

• Raw HTML: add the alt attribute to every <img> tag. For decorative images, use alt="" so screen readers skip them.
• WordPress: the media library has an Alt text field on every uploaded image. Fill it once and the value is reused everywhere the image is inserted.
• Shopify: in the product or page editor, click an image and use the Edit alt text option. Theme code that renders product images should pull image.alt.
• Wix or Squarespace: click the image in the editor and use the Alt text or Image description field in the side panel.
• Headless or framework sites: require an alt prop on every image component and lint for missing values during build.

Common causes and how to resolve them

• Attribute missing: add alt="" at minimum so the page validates. Replace with descriptive text on any image that conveys information.
• Alt text is the filename: "IMG_4837.jpg" tells the user nothing. Replace with a description of what is in the image.
• Alt text duplicates the visible caption: screen readers will read both, doubling the user's listening time. Differentiate the alt from the caption or empty the alt.
• Decorative images get descriptive alt text: background patterns and dividers should use alt="", otherwise screen readers narrate noise.
• Bulk imports left alt blank: a one-off audit of the media library or a CMS-side script can fill missing alt values from product names, captions, or asset descriptions.

Best practices

• Describe the function, not just the appearance: for a chart, describe what the chart shows. For a button image, describe what the button does.
• Keep it concise: aim for under 125 characters. Screen readers do not pause mid-sentence, so long alt text is exhausting to listen to.
• Skip "image of" or "picture of": the screen reader already announces it as an image.
• Include the focus keyword when natural: alt text is a minor on-page signal, but stuffing keywords in unnatural alt text harms both accessibility and ranking.

Google Analytics 4 is a free measurement platform that records visitor behavior, traffic sources, and conversion data. Installing it does not directly affect rankings, but the data it produces is essential for measuring SEO performance, identifying high-value pages, and prioritizing future optimization work. Fixing this issue means installing the GA4 tag site-wide and confirming events appear in your reports.

Example

<!-- Place inside <head> on every page -->
<script async src="https://www.googletagmanager.com/gtag/js?id=G-XXXXXXXXXX"></script>
<script>
  window.dataLayer = window.dataLayer || [];
  function gtag(){dataLayer.push(arguments);}
  gtag('js', new Date());
  gtag('config', 'G-XXXXXXXXXX');
</script>

Where to make the change

• Raw HTML: paste the GA4 snippet into the <head> of every page. A shared layout file is the cleanest place.
• WordPress: use a site-kit or analytics plugin, or paste the snippet into your theme's header file. Avoid duplicating the tag across multiple plugins.
• Shopify: add the GA4 measurement ID under Online Store, Preferences, Google Analytics, or install the official Google channel app.
• Wix or Squarespace: both platforms offer a GA4 measurement ID field in their analytics settings panel.
• Headless or framework sites: install via Google Tag Manager or use the framework's analytics integration so the tag fires on every route change.

Common causes and how to resolve them

• Tag not installed at all: install GA4 using the snippet above or the platform-specific path.
• Universal Analytics tag still in place: Universal Analytics stopped processing data on July 1, 2024. Replace any UA tag (UA-...) with a GA4 measurement ID (G-...).
• Tag fires only on the homepage: ensure the snippet is in a shared template loaded by every page, not pasted into one post.
• Cookie banner blocks the tag before consent: integrate Consent Mode v2 so GA4 receives anonymized signals before consent and full data after.
• Tag duplicated: two snippets on the same page double-count sessions. Audit with the Tag Assistant browser extension and remove duplicates.

Best practices

• Verify with real-time reports: after installing, open GA4's Realtime view and load the site to confirm events arrive.
• Use Google Tag Manager: for any site beyond the simplest, GTM gives you a single place to manage analytics, conversion tags, and third-party scripts without code changes.
• Configure key events: mark conversions (purchase, lead, signup) as key events so reports highlight what matters for SEO ROI.
• Link to Search Console: connecting GA4 to Search Console surfaces organic queries alongside on-site behavior in the same reports.

This test fails when the page's stylesheets do not use CSS media queries to adapt the layout to different screen sizes. Media queries are the primary mechanism for responsive design, allowing typography, spacing, and component arrangement to adjust gracefully across devices. Because Google now indexes the web mobile-first, the responsive mobile layout is effectively the version search engines crawl, evaluate, and rank.

Example

/* Mobile-first base styles */
.card { padding: 16px; font-size: 16px; }

/* Tablet and up */
@media (min-width: 768px) {
  .card { padding: 24px; font-size: 18px; }
}

/* Desktop */
@media (min-width: 1024px) {
  .card { padding: 32px; font-size: 20px; }
}

Where to make the change

• Stylesheets: add @media blocks for the breakpoints your design needs. Start with mobile-first base styles and layer larger screens on top.
• WordPress: most modern themes are responsive. If yours is not, switch to a current theme or add custom CSS for breakpoints.
• Shopify, Wix, Squarespace: all platforms ship responsive themes by default; failures usually point at custom CSS that hard-codes desktop widths.
• Headless or framework sites: CSS frameworks like Tailwind, Bootstrap, and CSS Modules all include responsive utilities; ensure you are using them.

Common causes and how to resolve them

• No media queries at all: add a few breakpoints based on your design. Common choices are 480, 768, 1024, and 1280 pixels.
• Fixed pixel widths everywhere: replace with relative units (rem, %, vw) and let media queries handle major layout shifts.
• Desktop-first styles overriding mobile: reorder so mobile styles are the base and larger breakpoints add desktop refinements.
• Modern layout primitives missing: CSS Grid and Flexbox often eliminate the need for many media queries by responding naturally to available space.

Best practices

• Mobile-first: base styles target mobile; min-width media queries layer enhancements for larger screens.
• Use container queries where supported: they let components respond to their container's size rather than the viewport, which is often more useful.
• Test on real devices: emulator views miss real-world issues such as touch target size and font rendering. Test on actual phones too.

This test fails when the site does not serve a branded, helpful page for missing URLs. A custom 404 keeps users on the site by offering navigation, search, and suggested links rather than dropping them at the browser's generic error screen. Fixing this issue means designing a 404 template, ensuring it returns the correct HTTP 404 status, and pointing your server at it.

Where to make the change

• Server configuration: point your web server at a custom 404 page. In Nginx, use error_page 404 /404.html;. In Apache, use ErrorDocument 404 /404.html.
• WordPress: create a 404.php template in your theme. WordPress invokes it automatically for missing URLs.
• Shopify: edit the 404.liquid template in the theme code editor.
• Wix or Squarespace: use the platform's built-in 404 page editor in site settings.
• Headless or framework sites: Next.js uses not-found.js, Astro uses 404.astro, and similar frameworks all have a convention for the missing-route page.

Common causes and how to resolve them

• No custom 404 at all: create one. The minimum is the site header, navigation, a clear "page not found" message, and links to popular sections.
• 404 page returns HTTP 200: a "soft 404" confuses search engines. Verify the response status with DevTools or curl, and configure the server to return 404 for missing routes.
• 404 page redirects to homepage: redirecting users to the homepage hides broken URLs from analytics and search engines. Show a real 404 instead.
• Generic browser error visible: the server is not invoking the custom template. Check the configuration directive.

Best practices

• Keep the site chrome: show the header, footer, and navigation so users do not feel lost.
• Offer next steps: a search box, popular links, or category navigation help users get back on track.
• Track 404s: log missing-URL hits in analytics so you can spot broken inbound links worth fixing or redirecting.
• Be clear about the error: "Sorry, that page does not exist" is better than vague messaging that confuses users.

This test reports on whether the page applies a nofollow directive that tells search engines not to follow outbound links. The nofollow attribute (and the related sponsored and ugc values) controls how link equity flows from your page. Fixing this issue means using the right rel value on each external link based on its purpose so signals are passed only where you intend.

Where to make the change

• Raw HTML: add rel="nofollow", rel="sponsored", or rel="ugc" to specific outbound links rather than blanket-applying them site-wide.
• WordPress: the block editor offers a "mark as nofollow" option per link, and SEO plugins can auto-tag external links by domain.
• Shopify, Wix, Squarespace: editor-generated links allow rel attribute toggles; manual HTML embeds need them set explicitly.
• Headless or framework sites: wrap external links in a component that decides the rel based on the link's classification.

Common causes and how to resolve them

• Site-wide nofollow on every external link: overly aggressive. Reserve nofollow for sponsored, untrusted, or user-generated content.
• Sponsored content not labeled: use rel="sponsored" on paid placements and affiliate links to comply with Google's link spam policy.
• User-generated content unmarked: comments, forum posts, and review user submissions should use rel="ugc".
• Trusted editorial links nofollowed: these should pass equity. Remove the nofollow.

Best practices

• Use the most specific value: sponsored for paid links, ugc for user content, nofollow for everything else you want to disclaim. They can be combined: rel="sponsored noopener".
• Do not nofollow internal links: "PageRank sculpting" with internal nofollow no longer works and just wastes crawl signal.
• Audit periodically: as content ages, sponsored relationships change. Review affiliate and partner links once a year.