What is assistive technology?
Assistive technology (AT) includes any device, software, or equipment that helps people with disabilities perform tasks. Understanding how AT works helps you create content that works for everyone.
Why this matters for content creators
When you understand how assistive technology interprets your content, you can make better decisions about structure, labeling, and formatting. This page provides an overview of common AT to help you test and improve your work.
Screen readers
Screen readers convert text and interface elements to speech or braille output. They're used primarily by blind and low-vision users.
Common screen readers
| Screen reader | Platform | Cost | Notes |
|---|---|---|---|
| NVDA | Windows | Free | Most popular free option; great for testing |
| JAWS | Windows | $1,000+ | Industry standard; most feature-rich |
| VoiceOver | macOS, iOS | Built-in | Included with all Apple devices |
| TalkBack | Android | Built-in | Included with Android devices |
| Narrator | Windows | Built-in | Basic screen reader included with Windows |
How screen readers navigate
- Headings: Users press H to jump between headings
- Links: Users press K or Tab to navigate links
- Landmarks: Users jump to main, nav, search regions
- Tables: Users navigate cell by cell with arrow keys
- Forms: Users Tab between form controls
- Lists: Screen readers announce list length and position
Testing with NVDA (free)
- Download from nvaccess.org
- Install and launch (runs portable or installed)
- Press Insert+Q to quit when done
- Use H to navigate headings, Tab for links/buttons
Screen magnification
Magnification software enlarges portions of the screen for users with low vision.
Common magnifiers
- ZoomText: Windows professional magnifier ($500+)
- Windows Magnifier: Built into Windows (free)
- macOS Zoom: Built into macOS (free)
- Browser zoom: Ctrl/Cmd + Plus to zoom
Design considerations for magnification
- Content should reflow at 200% zoom (no horizontal scrolling)
- Don't use tiny text (16px minimum for body)
- Ensure hover states work on touch devices
- Provide adequate spacing between interactive elements
- Avoid fixed-width layouts
Voice control
Voice control software allows hands-free computer use through spoken commands.
Common voice control tools
- Dragon NaturallySpeaking: Professional voice recognition
- Windows Speech Recognition: Built into Windows
- Voice Control (macOS): Built into macOS
- Voice Access (Android): Mobile voice control
Design considerations for voice control
- All interactive elements need visible, speakable labels
- Link text should be unique and descriptive
- Button labels should match visible text
- Avoid icons without text labels
Switch devices
Switch devices are simple buttons that emulate keyboard input, used by people with significant motor disabilities.
How switches work
- Single switch: Scans through options, user activates when desired item is highlighted
- Multiple switches: Different switches for different actions (select, next, back)
- Sip-and-puff: Breath-controlled switches
- Eye gaze: Tracks eye movement for selection
Design considerations for switch users
- All functionality must work with keyboard
- Focus indicators must be highly visible
- Avoid time limits or provide extensions
- Keep navigation efficient (don't require many keystrokes)
Text-to-speech (read aloud)
Text-to-speech tools read content aloud without full screen reader functionality. Used by people with dyslexia, learning disabilities, or anyone who prefers audio.
Common TTS tools
- Immersive Reader: Built into Microsoft Edge, Word, OneNote
- Read Aloud extensions: Browser add-ons for Chrome, Firefox
- Natural Reader: Online and downloadable TTS
- Built-in OS features: Windows Narrator read aloud, macOS text-to-speech
Design considerations
- Use proper document structure (headings, lists)
- Spell out abbreviations on first use
- Use simple, clear language
- Avoid text in images
Alternative input devices
Many users rely on alternatives to standard keyboards and mice:
- Ergonomic keyboards: Split, angled, or one-handed designs
- On-screen keyboards: Virtual keyboards operated by mouse or gaze
- Head pointers: Headworn devices that control cursor
- Mouth sticks: For typing with mouth-held pointer
- Trackballs: Alternative to mouse for limited hand mobility
- Joysticks: Game-style controllers for cursor movement
All of these ultimately interact with your content through keyboard commands, which is why keyboard accessibility is fundamental.
Braille displays
Refreshable braille displays show screen content as raised braille dots, used alongside or instead of speech output.
How braille displays work
- Typically 40-80 braille cells wide
- Connects to screen reader (JAWS, NVDA, VoiceOver)
- Shows one line at a time from screen
- User navigates with buttons on display
Design considerations
- Same as screen reader considerations
- Keep line lengths reasonable
- Don't use ASCII art or visual spacing for layout
Testing with assistive technology
Recommended testing approach
- Keyboard only: Navigate entire interface without mouse
- Screen reader: Test with NVDA (Windows) or VoiceOver (Mac)
- Zoom: Test at 200% browser zoom
- High contrast: Test Windows High Contrast mode
Free tools for testing
- NVDA: Free screen reader for Windows
- VoiceOver: Built into macOS and iOS
- TalkBack: Built into Android
- Browser zoom: Ctrl/Cmd + Plus
- Windows High Contrast: Settings → Accessibility → High contrast