Mobile Friendliness Checker

📖 About this tool

Mobile friendliness is both a ranking factor and a key influence on bounce rate for phone users. This tool parses pasted HTML locally in the browser and checks eight common problems: whether a viewport exists and includes width=device-width, whether user zoom is disabled, whether any font size is below 12px, whether any tap target is under 44px, whether any fixed width exceeds 320px, whether legacy object or embed elements remain, whether images are missing alt text, and whether the source is unusually heavy. Each item is marked Pass, Warning or Fail with an explanation, and the results roll up into a score out of 100. The source is parsed only on your own machine and is never uploaded. Typical uses include self-checking adaptation after a redesign, tracking down horizontal scrolling on phones, verifying that zoom has not been disabled by mistake, and running an adaptation audit before handing a site to a client.

✨ Features

• Eight metrics：Viewport, zoom, font size, tap targets, fixed widths, plugins, alt text and page weight
• Local parsing：Parsed with the browser DOMParser — the source is never uploaded
• Score out of 100：Points deducted by severity, with a total and an overall verdict
• Pinpoints problems：Each issue reports a concrete count so you can fix it precisely
• One-click sample：Built-in sample source with several problems, to show how the checks work

🚀 How to use

1. Paste the page HTML source;
2. Click Run check;
3. Review each verdict and explanation;
4. Fix the issues and check again.