Part of the Accessibility audit
Check your mobile viewport settings
Without a viewport meta tag, mobile browsers shrink your site to fit a tiny screen. SiteCurl checks that the tag exists and does not block zooming.
No signup required. Results in under 60 seconds.
What this check does
SiteCurl checks every page for a <meta name='viewport'> tag and verifies two things. First, the tag exists. Without it, mobile browsers render the page at desktop width (usually 980px) and shrink everything down, making text unreadable without zooming.
Second, SiteCurl checks that the tag does not disable zooming. Settings like user-scalable=no or maximum-scale=1 prevent visitors from pinching to zoom. People with low vision depend on zoom to read text and see details. Blocking it makes the page inaccessible.
A viewport tag with width=device-width, initial-scale=1 and no zoom restrictions passes the check.
How this shows up in the real world
In the early days of smartphones, websites were designed for desktop screens. Mobile browsers needed a way to display those wide pages on small screens. The solution was to pretend the screen was 980px wide and scale everything down. This worked for desktop sites, but it made text tiny and buttons hard to tap.
The viewport meta tag changed this. By setting width=device-width, you tell the browser to use the actual screen width for layout. A phone with a 390px wide screen lays out the page at 390px, not 980px. Combined with responsive CSS, this makes text readable and buttons tappable without any zooming.
The zoom issue is separate but related. Some developers add user-scalable=no or maximum-scale=1 to prevent visitors from zooming in. The stated reason is usually 'it breaks the layout' or 'it looks better without zoom.' But blocking zoom removes a vital tool for people with low vision. They cannot enlarge text, they cannot zoom into images, and they cannot adjust the page to their visual needs.
WCAG 2.2 addresses this directly. Success Criterion 1.4.4 (Resize Text) requires that text can be resized up to 200% without loss of content or functionality. Blocking pinch-to-zoom violates this requirement on mobile devices.
Why it matters
A missing viewport tag makes your site look like a desktop page crammed onto a phone screen. Text is tiny. Buttons are too small to tap. Forms are impossible to fill in. Most visitors leave immediately because the site looks broken.
A viewport tag that blocks zooming is a different problem with the same result: people cannot use the site. Low-vision users who need to zoom in are locked out. This is both an accessibility failure and a usability failure for anyone who wants a closer look at an image, a chart, or small text.
Google uses mobile-friendliness as a ranking factor. Pages without a proper viewport tag are flagged as not mobile-friendly in Google Search Console. This can lower rankings on mobile search, which is now the majority of web traffic.
Who this impacts most
Every website with mobile visitors needs a viewport meta tag. Since mobile traffic exceeds desktop traffic for most sites, this is not optional. A site without the tag is essentially broken on more than half of its visits.
Sites that block zooming affect low-vision users directly. According to the WHO, over 2.2 billion people globally have a vision impairment. Blocking zoom removes their primary tool for reading content on mobile devices.
Older sites that were built before responsive design became standard are the most likely to be missing the viewport tag entirely. Sites built in the early 2010s or before may still have a fixed-width layout with no viewport setup.
How to fix it
Step 1: Add the viewport meta tag. In your HTML <head>, add: <meta name='viewport' content='width=device-width, initial-scale=1'>. This tells mobile browsers to use the real screen width and start at 100% zoom.
Step 2: Remove zoom-blocking settings. If your viewport tag includes user-scalable=no or maximum-scale=1, remove those values. The tag should allow visitors to zoom in as needed. A maximum-scale of 5 or higher is acceptable. Anything below 2 is flagged as restrictive.
Step 3: Check your CMS or framework. In WordPress, the viewport tag is usually in header.php or set by the theme. In React, check index.html or the root layout component. In Rails, check the application layout. Most modern frameworks include the correct tag by default.
Step 4: Test on a real device. Open your site on a phone. The text should be readable without zooming. Pinch to zoom should work. If the text is tiny or zoom is blocked, the tag is missing or wrong.
Common mistakes when fixing this
Adding user-scalable=no to prevent layout issues. If zooming breaks your layout, the layout needs fixing, not the zoom. Use responsive CSS (media queries, flexible grids, relative units) to handle different sizes. Never disable zoom to work around a layout problem.
Setting maximum-scale=1 to prevent double-tap zoom. Some developers disable zoom to prevent the double-tap zoom behavior on mobile. This is a cosmetic preference that hurts users with low vision. If double-tap zoom causes a specific interaction problem, solve it with CSS touch-action, not by blocking all zooming.
Forgetting the tag on some pages. If your site uses multiple templates, some may include the viewport tag and others may not. SiteCurl checks every page in your scan to catch templates that are missing it.
Setting width to a fixed pixel value. width=1024 forces the page to render at 1024px wide on all devices. Use width=device-width so the page adapts to the actual screen size.
How to verify the fix
After adding or fixing the viewport tag, run another SiteCurl scan. The check should pass if the tag is present and does not block zooming. For a quick manual check, view the page source and search for meta name='viewport'. The content should include width=device-width and should not include user-scalable=no.
On a phone, try pinching to zoom. If the page zooms in smoothly, the setting is correct. If the page does not respond to pinch gestures, zoom is still blocked.
The bottom line
The viewport meta tag makes your site work on mobile. Without it, pages render at desktop width and shrink to fit. With zoom disabled, low-vision users cannot enlarge content. Add the tag with width=device-width, initial-scale=1 and remove any zoom restrictions.
Example findings from a scan
Viewport meta tag missing on /services
Viewport disables zooming with user-scalable=no
maximum-scale=1 blocks pinch-to-zoom on /
Related checks
Frequently asked questions
What does the viewport meta tag do?
It tells mobile browsers how to scale the page. Without it, browsers assume the page is 980px wide and shrink it to fit the screen. With width=device-width, the page uses the phone's actual screen width for layout.
Why should I not block zooming?
People with low vision need to zoom in to read text and see details. Blocking zoom with user-scalable=no or maximum-scale=1 removes their primary tool for using your site on mobile. WCAG requires that text can be resized up to 200%.
Does the viewport tag affect SEO?
Yes. Google uses mobile-friendliness as a ranking signal. Pages without a proper viewport tag are flagged as not mobile-friendly, which can lower rankings on mobile search results.
Can I check my viewport tag without signing up?
Yes. The free audit checks the viewport meta tag in a full seven-category scan. No signup needed.
Check your viewport settings now