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web validator

Viewport Meta Validator

Validate viewport meta tags for mobile-friendly settings and accessibility.

Results

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Status
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Details
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Width
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Initial scale
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User-scalable
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Maximum scale
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Issues
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How to use this validator

  1. Paste the meta viewport tag or head snippet.
  2. Run validate to check width/device-width and scale values.
  3. If warned (e.g., user-scalable=no), adjust for accessibility and re-run.

Rules & checks

Requires width=device-width for responsive layouts.

initial-scale must be numeric if set.

Warns on user-scalable=no or maximum-scale < 1 (accessibility concerns).

Runs client-side only.

Inputs explained

  • HTML head or meta tag

    Paste the viewport meta tag or head snippet. We parse the content attribute for width/scale settings.

When to use it

  • QA landing pages for mobile readiness
  • Check CMS templates for correct viewport tags
  • Support teams validating user-submitted HTML

Common errors

  • Missing width=device-width
  • Non-numeric initial-scale
  • user-scalable=no blocking zoom
  • maximum-scale set below 1

Limitations

  • Structural check only; does not measure actual layout responsiveness.

Tips

  • Avoid disabling zoom unless absolutely necessary
  • Set width=device-width to prevent narrow render
  • Keep initial-scale reasonable (e.g., 1) for accessible zoom behavior

Examples

Valid

  • <meta name="viewport" content="width=device-width, initial-scale=1">

Missing width

  • <meta name="viewport" content="initial-scale=1"> -> flagged

Non-accessible

  • user-scalable=no -> warned

Deep dive

This viewport validator checks width=device-width, scales, and accessibility flags entirely in your browser.

Use it to keep pages mobile-friendly before launch without uploading HTML.

FAQs

Is anything uploaded?
No. Parsing is local and clears on refresh.

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