The launch-readiness audit

Mobile viewport: don't ship a desktop-shrunk page

Most first visits come from a phone, especially via social links. Without a viewport meta tag the page renders desktop-shrunk and unusable. Learn the one line that fixes it.

Last updated 2026-07-19

This weight-5 check confirms your page has a viewport meta tag — the one line that tells phones to render at device width instead of shrinking a desktop layout.

What Actuant checks

  • A <meta name="viewport"> in the head → pass.
  • Missing → fail ("broken on phones, where your traffic is").

Its companion, Theme color (weight 1), checks for a theme-color meta so mobile browser chrome matches your app.

Why it matters

Most first visits — especially from social links — are on a phone. Without a viewport meta, the browser renders your page at a desktop width and zooms out, so text is tiny and buttons are unhittable. Visitors bounce before they read a word.

How to fix it

Add one line to your document head. Most frameworks include it by default, but exported/static builds and hand-rolled templates often drop it.

add to <head>html
<meta name="viewport" content="width=device-width, initial-scale=1" />

Adding the tag isn't the same as being responsive. After you add it, actually load the page on your phone and check nothing overflows.