Verify that the website is responsive

Mobile-first indexing has been Google's default since 2021. Google indexes and ranks your site based on its mobile version, not the desktop version. If your Webflow site looks fine on a large monitor but breaks on a 390px screen, the broken version is what Google is evaluating.

In Webflow, responsiveness is built into the design process through breakpoints. But designing for breakpoints and actually being responsive are different things. It's common to build out the desktop view, do some cleanup on mobile, and call it done. In practice, that often leaves content that's technically visible on mobile but barely usable: text that's too small, buttons too close together, images that don't resize, or navigation that doesn't work with a thumb.

The verification checklist before going live: open every template page and key static page in Webflow Designer's mobile view. Check all mobile breakpoints you've customized. Things most likely to break: hero sections with fixed heights that clip text on smaller screens, navigation menus that collapse but lack a working hamburger menu, images that overflow the container, and columns that were meant to stack but don't.

Then test in a real browser on a real phone. Webflow Designer's preview is accurate but not identical to a real browser rendering. Tap every button, scroll every section, open the navigation. Ten minutes per template page, and it catches things the designer view misses.

Check your Core Web Vitals in Google Search Console under Experience → Core Web Vitals. Google measures LCP, INP, and CLS on mobile specifically. A site that passes on desktop but fails on mobile will show "Poor" status in this report. Pay particular attention to Cumulative Layout Shift — elements that move after load are a common Webflow issue caused by images loading without explicit dimensions.

Two specific mobile usability issues Google flags in GSC under Experience → Mobile Usability: text too small to read without zooming, and tap targets too close together. Both are ranking signals, not just UX notes.

For broader testing, Chrome DevTools lets you simulate any screen size by entering exact pixel widths. Common sizes worth testing: 375px (older iPhones), 390px (iPhone 14), 360px (common Android). If the design holds at these widths, you're covering the majority of mobile users.

After launch, check the Mobile Usability report in GSC monthly. Mobile issues are often introduced by new CMS pages or content changes that weren't previewed at mobile widths before publishing.