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ValidateHTML

Missing Viewport Meta Tag

The viewport meta tag tells mobile browsers how to scale the page. Without it, mobile browsers render the page at a desktop width (usually 980px) and then zoom out, making everything tiny and unreadable.

Why It Matters

Missing the viewport meta tag is the #1 reason sites don't look responsive on mobile — even with perfect CSS media queries. Google's mobile-first indexing also checks for this tag; missing it can hurt your mobile search rankings.

Code Examples

❌ Invalid
<head>
  <title>My Page</title>
  <!-- No viewport tag -->
</head>
✓ Valid
<head>
  <title>My Page</title>
  <meta name="viewport" content="width=device-width, initial-scale=1">
</head>

How to Fix

  • 1Add <meta name="viewport" content="width=device-width, initial-scale=1"> to your <head>.
  • 2Don't use maximum-scale=1 or user-scalable=no — they break accessibility by preventing zoom.
  • 3Place the viewport tag early in <head>, before any CSS or scripts.
  • 4This is a one-time fix — add it to your base template and it applies everywhere.

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