Low Vision Design is the Overlooked Middle Ground in Accessibility
People often forget that accessibility is about meeting the needs of a spectrum of user's abilities, especially when it comes to vision, the middle ground is often overlooked. When considering vision abilities there is more to be considered between users who are sighted and users who use screen readers. It's not binary.
There's an entire spectrum of vision loss between "perfect sight" and "completely blind" and most digital products ignore it entirely. People with low vision don't use screen readers, and have other tools at their disposal to help. They see your interface, but they see it differently. Color might wash together, text might blur, and contrast might disappear. Right now, your product is probably making their experience worse, not better.
According to the CDC, about 12 million Americans have vision impairment. That's roughly 3.6% of the U.S. population. Not everyone uses a screen reader. Most of them navigate the web the same way you do and they just need your design to meet them halfway. 1
Why Low Vision Design Gets Ignored
The accessibility conversation is dominated by screen reader and color contrast when testing. Low vision design doesn't fit neatly into that process because there's no single "low vision user" to design for. There are dozens of different vision conditions, and each one interacts with your design in different ways.
That complexity is why it's overlooked, but that's also why it matters. Getting low vision design right isn't just about accessibility compliance, it's about good design. The principles that make your product usable for people with low vision make it better for everyone, like sharper contrast, readable typography, clear information hierarchy, and meaningful color usage.
The Spectrum of Low Vision
So what do we need to consider?
Color Blindness (Red-Green Deficiency)
About 8% of men and 0.5% of women have some form of color blindness and the most common is red-green color blindness. These users don't see colors in black and white, they see a different color palette. A red button and a green button might look almost identical to them.
This is relatively easy to address. Never rely on color alone to communicate information. Use a combination of color, text, icons, or patterns. If your form has errors highlighted in red, add an error icon or prefix the label with "(error)". If your graph uses red and green to show loss and gain, add line patterns or numbers. If your charts have multiple colors that would sit adjacent to each other, make sure the hues are distinct, or add a border between them.
Low Contrast (Partial Sight)
The most common form of low vision is partial sight, a reduced visual acuity combined with reduced contrast sensitivity. These users can see, but some things become washed out. Contrast here is everything. A pale gray on white background is indistinguishable to them.
WCAG 2.1 requires 4.5:1 contrast for normal text and 3:1 for large text. That's the minimum baseline. If you're serious about low vision users you should hit 7:1. 2
Visual Field Loss (Tunnel Vision & Scotomas)
Some people experience tunnel vision where they can only see a small area in the center of their visual field. Others have scotomas which are blind spots scattered across their vision. They can't see your entire interface at once.
For tunnel vision users, crucial information needs to be in the center of the screen. Navigation, critical actions, and primary content should all be front and center. Don't hide important information in the periphery. For scotoma users, make sure essential elements can be found through multiple paths. Don't rely on a single button or icon in a position that might fall into their blind spot.
There are users that use screen magnifiers. If you've never used one, you should really give it a try. For these users, actions should be in close proximity and have a clear relationship. It's difficult trying to hunt down a submit button because it's nowhere near the end of a form you're trying to fill out.
Blur & Low Acuity
Some people have low visual acuity where everything is blurry, like looking through slightly frosted glass. They need larger text, more spacing, and heavier font weights.
The web's default 16px font size is fine for sighted users, but people with low acuity, even 18-20px makes a difference. Increase line height to 1.5 or 1.6 and use font weights of 500 or higher. Make interactive elements bigger, a 44x44px minimum touch target helps everyone, especially low vision users hunting for small buttons.
Light Sensitivity
Some users, especially those with cataracts or albinism, struggle with bright, high-contrast interfaces. They need softer contrast and warmer tones. This is why dark mode exists and why it should be a real option in your product, not an afterthought.
Practical Design Principles for Low Vision
Now that you understand the spectrum, here's what to actually do:
1. Test with Real Contrast Ratios
Don't just meet WCAG minimums. Test your color combinations with tools like WebAIM Contrast Checker or Contrast Ratio. Aim for at least 7:1 on primary text. When in doubt, go darker or lighter.
2. Size Typography Thoughtfully
Base font size should be 16px minimum, with line height of 1.5+. For headings and important information, bump up to 18-20px. Don't just increase size, increase the weight too. Use 500 or 600 weight fonts and avoid light weights entirely.
3. Never Rely on Color Alone
Use color to enhance information, not communicate it. Add icons, text labels, patterns, or borders. If your chart shows profit in green and loss in red, add a legend or different line patterns. If you're flagging warnings, pair the color with an icon and text.
4. Create Breathing Room
Add generous padding and margins. Space isn't wasted space... it's clarity. Low vision users benefit from visual separation. Buttons need breathing room. Text blocks need margins. Don't pack information densely.
5. Use High-Quality Typography
Font choice matters more than people think. Sans-serif fonts with clear letterforms work better than decorative or thin fonts. Arial, Helvetica, Verdana, and system fonts are safer bets than quirky typefaces. Avoid italics for body text because they reduce contrast and clarity.
6. Test with Zoom
Low vision users often zoom their browser to 200% or higher. Make sure your interface works at 200% zoom without horizontal scrolling. Test it. Your responsive design that works on mobile doesn't guarantee it'll work at zoom levels.
7. Provide Dark Mode
Or at minimum, respect the prefers-color-scheme media query. Some users need darker interfaces and others need brighter ones. Let them choose.
8. Make Focus Clear
Keyboard users with low vision rely on a visible focus indicator. Don't remove it or make it subtle. A 2-3px border or outline is standard. Make it stand out from your design.
The Business Case
Designing for low vision is good product design. The same principles make your product clearer, faster, and more usable for everyone. Increased contrast helps readability, larger type is easier to scan and spacing reduces cognitive load. Removing reliance on color alone makes your product more accessible across different contexts... colorblind users, users on phones outside in bright sunlight, users printing your pages... They're not using your products in your most ideal conditions.
And that market of 12 million Americans with vision impairment? They have money, they have problems they want solved, and most products make their lives harder.
They're not asking for charity. They're asking for competence and you need to think more about low vision design to build better products.