Why Test with a Screen Reader?
The first time I ran NVDA on a site I thought was "accessible," I was shocked. Content was announced in a nonsensical order, buttons had no names, and the contact form was completely unusable. The automated tools had given me a decent score, but the real-world experience was something else entirely. That's why screen reader testing is irreplaceable: it reveals reading order issues, poorly announced components, and blocking interactions that no automated tool can catch.
NVDA: Free Windows Reader
NVDA (NonVisual Desktop Access) is free and open source. Download it from nvaccess.org -- installation takes 2 minutes. When it starts talking, don't panic -- press Ctrl to silence it while you get organized. You don't need to learn every command. Here's what covers 90% of testing: H for headings, D for landmarks, F for forms, G for images, Tab for interactive elements, Insert+F7 for the full element list. Use Firefox for the best compatibility -- that's the reference combination.
Testing Walkthrough with NVDA
Here's the test routine I use every time. Takes 15 minutes and covers the essentials: navigate headings with H (is the hierarchy logical?), check landmarks with D (header, nav, main, footer present?), test forms with F (are labels announced?), review images with G (relevant alt or "image with no description"?), tab through interactive elements (any keyboard traps?), and test interactive components like menus and modals (are states announced?).
VoiceOver: Built into Mac
If you're on a Mac, you already have a screen reader. Activate VoiceOver with Cmd+F5. It uses a modifier key called VO (Ctrl+Option) -- lots of keys, but you get used to it fast. VO+right/left arrow to navigate elements, VO+Space to activate, VO+U for the Rotor (your secret weapon -- instant overview of all headings, links, forms, landmarks). Test with Safari for best compatibility.
Common Testing Mistakes
When I train developers on screen reader testing, it's always the same traps: testing only with Chrome (use Firefox+NVDA or Safari+VoiceOver for reliable results), not understanding the difference between browse mode and focus mode (this is the number one confusion for beginners), comparing what you hear with what you see (close your eyes -- does the audio alone make sense?), and stopping at automated tools thinking they're enough (they're a complement, not a replacement).
15 minutes of screen reader testing teaches you more about a site's accessibility than hours of automated scanning. That's not an exaggeration -- it's experience talking.