Definition
Screen reader testing is the process of loading an email into screen reader software — such as VoiceOver on Mac, NVDA on Windows or TalkBack on Android — and verifying that the content is read in a logical order, all images have descriptive alt text, interactive elements are reachable via keyboard and the email's core message is communicated without visual cues.
Many email accessibility issues are invisible in a visual preview but immediately apparent to a screen reader user. Headings that are styled to look like headings but are not marked up as <h1> or <h2> elements, images without alt attributes that contain critical information and links labelled "click here" all create a confusing or unusable experience for screen reader users.
What to Test
- Reading order: does the screen reader announce content in the intended sequence?
- Heading hierarchy: are heading levels logical and informative?
- Image alt text: do all content images have meaningful descriptions?
- Link purpose: does each link label clearly describe its destination?
- Interactive elements: can all buttons and form fields be accessed via keyboard?
Best Practices
- Include screen reader testing in your pre-send QA checklist alongside visual rendering tests
- Test with at least two screen readers across different platforms — behaviour varies significantly between tools
- Do not rely on visual inspection to catch accessibility issues; screen reader testing reveals problems no visual review can
- Document accessibility findings and share them with the design team to prevent recurring issues
Related Glossary Terms
Accessible CTA (Email)
An accessible CTA is a button or link coded with sufficient colour contrast, visible focus states, descriptive screen-reader text, and a minimum touch target of 44×44 pixels.
Dark Mode
Dark mode in email refers to how email clients render messages when the recipient has dark mode enabled. It affects colour display, image rendering, and readability. Designers use CSS media queries and hybrid coding techniques to control the dark mode appearance.
Drag-and-Drop Email Editor
A drag-and-drop email editor is a visual interface that allows marketers to build email layouts by dragging content blocks into place without writing HTML or CSS code.
Email A/B Test Confidence Level
The confidence level in an email A/B test indicates the probability that the observed result is genuine and not due to random chance, with 95% being the standard threshold.
Email A/B Test Examples
Email A/B test examples show practical testing scenarios that help marketers improve open rates, click-through rates, and conversions through data-driven experimentation.
Email A/B Test Minimum Detectable Effect
The minimum detectable effect (MDE) is the smallest improvement an A/B test can reliably detect given the available sample size, directly affecting how long a test must run.