Services · Testing types
How Your Site Holds Up at 400% Zoom
For the team that wants the site holding together at the zoom levels low-vision users actually run, not just looking sharp at 100%.
What We Keep Finding
Most low-vision users do not run a screen reader. They run zoom, and not the polite 110% kind. Browser zoom at 200% and 400%, larger system text, custom spacing overrides. Now picture your site there. Does the content reflow to fit, or does every line demand sideways scrolling? Does the menu still open, or does the sticky header swallow half the screen?
WCAG wrote two quiet rules for exactly this, reflow and text spacing, and chances are pretty good nobody has ever tested your site against either. Both are narrower than teams fear, which is worth knowing before somebody rebuilds a layout that was fine. Reflow does not require your content to stack into a single column, and it expressly allows two-dimensional scrolling for the things that need it, so maps, diagrams, video and data tables are not failures for scrolling sideways. Text spacing does not ask you to set the spacing yourself. It asks whether your content survives when a reader sets it.
The number underneath 400% is worth having straight too, because without it two testers get two answers. The target is content working at a width equivalent to 320 CSS pixels, and 320 is what you get from a 1280-pixel window at 400% zoom. That is the width we test to, and the report names the browsers and settings so any finding can be replayed on your side.
What We Check
- Zoom every audited page to 200% and 400% and log what clips or collides
- Verify content reflows without forcing scrolling in two directions
- Apply the text spacing overrides and watch for overlap and cut-off labels
- Test the sticky parts at high zoom, so headers, banners, chat buttons
- Confirm text scales to 200% without controls falling off the screen
What You Get
Every service on this site runs the same three-pass engine: an automated scan, an expert review of all 55 WCAG 2.2 A and AA rules, and a hands-on session with a professional blind screen-reader user. You get one report with every finding screenshotted, ranked by user impact, and linked to its fix. Your team fixes, we verify: the re-audit is half price within 3 months.
The format is not a mystery either. Read the sample report before you spend anything.
The Honest Limit
One honest limit and one thing the free scan structurally cannot do for you here. The limit is that zoom behavior shifts a little between browsers, and we test the mainstream desktop ones rather than every pairing in existence, with the exact browsers and settings named in the report. The free scan is the sharper boundary. It renders at a single desktop size, so nothing at 320 CSS pixels is ever evaluated and no reflow finding can come out of it, whatever the score says. This is the one pass where a clean free report tells you nothing at all.
What It Costs
Rapid Audit: $499, up to 10 pages you pick, report in 5 business days. Standard Audit: $1,499, up to 25 pages in 10 business days. Flat rates, no discovery calls, and a real blind screen-reader user on every engagement. Pick your pages. We bring the humans.
Worth Reading Next
Related on this site
Guides, checklists, tools, and terms that go with this service.