Text Resize, Zoom and Reflow: What Ontario's AODA and WCAG Require So Low-Vision Customers Can Read Your Site (2026)

Not everyone who struggles to read your site is blind. Far more of your customers have low vision: they can see the screen, but they need the text bigger, the lines more spaced, or the whole page zoomed in before they can read it. They don't reach for a screen reader. They reach for the zoom control, or their browser is already set to enlarge every page they open. The real question is what happens to your site when they do. On a well-built page the text grows and the layout reflows into a single readable column. On a poorly built one the text gets clipped, columns overlap, buttons slide off-screen, and the customer ends up dragging the page sideways to finish one sentence. Most of them just leave. And because this only shows up when someone actually enlarges the page, it's the kind of failure that a quick glance at your site will never reveal.

Key facts

• WCAG 1.4.4 Resize Text is Level AA and part of WCAG 2.0 (Web Content Accessibility Guidelines): text must be resizable up to 200% with no loss of content or functionality, and without the user needing assistive technology (W3C).
• WCAG 1.4.10 Reflow is Level AA, introduced in WCAG 2.1: content must reflow to a single column at a width of 320 CSS pixels (the equivalent of 400% zoom on a 1280-pixel-wide screen) without forcing the user to scroll in two directions (W3C).
• WCAG 1.4.12 Text Spacing is Level AA, also from WCAG 2.1: nothing should break when a reader overrides spacing to line height 1.5×, paragraph spacing 2×, letter spacing 0.12×, and word spacing 0.16× the font size (W3C).
• WCAG 1.4.5 Images of Text is Level AA and part of WCAG 2.0: use real text, not pictures of text, so it stays sharp and resizable when enlarged (W3C).
• Ontario's IASR (Integrated Accessibility Standards Regulation, O. Reg. 191/11) s.14 requires organizations with 50 or more employees to make public websites conform to WCAG 2.0 Level AA, and the next ACR (Accessibility Compliance Report) for organizations with 20 or more employees is due December 31, 2026 (ontario.ca).

What does Ontario's AODA actually require for text resize and zoom?

Ontario's AODA (Accessibility for Ontarians with Disabilities Act) sets the policy and the IASR sets the technical bar: WCAG 2.0 Level AA for public websites at 50 or more employees. Two of the criteria low-vision users depend on sit squarely inside that legal floor. 1.4.4 Resize Text means your text has to survive being doubled in size without anything breaking, and 1.4.5 Images of Text means you can't bake your headings, prices, or button labels into a JPG that blurs and can't be enlarged. Those are already required, today, at WCAG 2.0 AA.

The two criteria that matter most when someone really cranks up the zoom, 1.4.10 Reflow and 1.4.12 Text Spacing, arrived later, in WCAG 2.1, and are part of the current WCAG 2.2. They are not in the bare WCAG 2.0 floor the law names. That is the same law-versus-best-practice gap covered in WCAG 2.0 vs 2.2 in Ontario and what changed with WCAG 2.2: the legal minimum is 2.0, but the standard worth building to is 2.2, and a layout that reflows cleanly is one of the clearest reasons why.

How do low-vision customers read your site, and where does it break?

There are three habits a low-vision visitor brings to your page, and each one maps to a criterion above.

• They zoom the whole page (Ctrl-plus on Windows, Cmd-plus on Mac), often a long way. At 400%, equivalent to a 320-pixel viewport, the page should collapse into a single column they read by scrolling down only. A fixed-width layout that refuses to reflow forces them to scroll left and right on every line, which is exactly what 1.4.10 Reflow exists to prevent.
• They enlarge just the text, through browser settings or a reading tool, up to and past 200%. If your design uses fixed-height boxes or tightly packed rows, the enlarged text gets clipped or overlaps, which fails 1.4.4. The same brittleness shows up when a reader applies their own spacing for dyslexia or eye strain, the case 1.4.12 Text Spacing covers.
• They rely on real text staying crisp. A promo banner with the sale price baked into an image turns to mush the moment it's magnified, while real text stays sharp at any zoom. That's 1.4.5, and it's the same principle behind keeping your headings and structure as real markup rather than styled pictures.

This overlaps heavily with responsive design. A site that reflows neatly onto a narrow phone usually reflows neatly at high zoom too, because both collapse the content into a narrow viewport, which is why this sits right next to mobile and touch accessibility. And it belongs in the same family as color contrast: both are the low-vision half of accessibility, the customers who can see your page but can't comfortably read it. One thing it is not is something a bolt-on widget can solve. A "bigger text" button bolted on top of a fixed-width layout doesn't make that layout reflow, because an overlay can't rebuild your CSS; the responsive structure has to live in the page itself.

How do you check whether your site survives zoom, and what's the risk if it doesn't?

You can test the core of this yourself in about two minutes, with no tools at all:

1. Open a page that matters (your home page, a product, your checkout or contact form). Hold Ctrl or Cmd and press plus until the browser reads 400%. Does the content reflow into one column you can read by scrolling straight down, or are you dragging the page sideways to finish each line (1.4.10)?
2. Reset, then zoom to 200% and check that nothing is clipped, overlapping, or cut off the edge of the screen (1.4.4).
3. Hunt for any text baked into images: banners, pricing graphics, "sale" badges. Does it go blurry when you zoom? That text should be real, selectable text (1.4.5).
4. Walk a real task at high zoom, finding a product, filling the form, reaching checkout, the same end-to-end test you'd run for keyboard access.

The stakes are the same as for any access barrier. In Ontario the AODA has no private right of action, so an individual cannot sue under it directly. The live route for a person is the HRTO (Human Rights Tribunal of Ontario), which hears complaints under the Ontario Human Rights Code, and a low-vision customer who can't read your prices or finish a purchase a sighted customer can finish has a plausible claim of unequal access to goods and services, the path laid out in how an HRTO complaint plays out. If you sell into the United States, layout that collapses at zoom is among the issues cited in ADA (Americans with Disabilities Act) litigation, part of the more than 5,000 digital accessibility lawsuits filed across US courts in 2025 (UsableNet). The durable answer is the same one that holds for every gap: documented remediation, a dated record of what you found and fixed, which is also what an honest ACR should reflect by December 31, 2026. And because whether a page is genuinely readable at 400% is a human judgment, this is one more reason a scan is not an audit: a crawler can flag an image of text or a fixed width, but it can't tell you whether a real customer can actually read your page once it's enlarged.

See whether your site flags resize, layout, or other accessibility issues, free Vayle Report, about 30 seconds: vayle.art. It detects overlay widgets, surfaces real WCAG failures, and tells you exactly what legally applies to your organization in Ontario. No obligation.

Vayle is a remote-first accessibility-engineering studio serving Ontario. General information, not legal advice.