Mobile SEO Checker

Google switched to mobile-first indexing in 2019. What that means in practice: when Googlebot crawls your site, it uses the smartphone version. Whatever content is missing on mobile is missing from Google's view of your site — even if it's visible on desktop.

This catches a lot of older small business sites. Owners assume the desktop version is "the site" and a stripped-down mobile menu is fine. But if your mobile version hides product details, testimonials, or service pages, Google effectively doesn't see them. They can't rank.

The fix is to use a responsive design where the same HTML is served to every device and the layout adapts via CSS. Separate m.yourdomain.com setups are obsolete and actively harmful to SEO — don't let any developer build you one in 2026.

Google uses three measurable metrics, collectively called Core Web Vitals, as direct mobile ranking signals.

LCP (Largest Contentful Paint) is how long it takes for the biggest visible element to render — usually your hero image or main heading. Target under 2.5 seconds. Most slow LCPs come from oversized hero images and uncompressed photos.

INP (Interaction to Next Paint) measures how quickly the page responds when a user taps something. Target under 200 ms. Slow INP usually means too much JavaScript running on the main thread — typically from heavy page builders or unused plugins.

CLS (Cumulative Layout Shift) measures visual stability — how much the page jumps around while loading. Target under 0.1. Common causes: images without width/height attributes, fonts that swap in late, or ads that load above existing content. Easy to fix once you know.

Test all three at pagespeed.web.dev with your URL, and always look at the mobile tab — desktop scores are flattering and misleading.

Beyond raw performance, Google demotes mobile pages with specific usability problems. The ones we check for:

Intrusive interstitials. Popups that cover the main content immediately after a user arrives from search are penalized. Cookie banners and age gates are exempt; "sign up for our newsletter" full-screen overlays are not.

Tap targets too close together. Buttons and links smaller than ~44×44 px or packed too tightly cause mis-taps. Common offenders are menu items, footer link lists, and pagination.

Text too small to read. Body text under 16 px forces users to pinch-zoom. Google sees this and demotes the page.

Horizontal scrolling. If content runs wider than the viewport on a phone — usually because of a fixed-width element or an oversized image — the page is flagged as not mobile-friendly.

Fix these and you'll usually see rankings respond within 2–4 weeks of Google's next crawl.