What you will learn
- Test the site across screen sizes, browsers and real devices
- Check keyboard access, contrast, alt text and headings
- Confirm links, forms, metadata and the 404 page all work
Testing catches the problems visitors would otherwise find for you. Open the site in at least two different browsers and on a real phone, not only in device mode. Check every page at narrow, medium and wide widths. Look for text that overflows, images that stretch, buttons that are hard to tap and content that is hidden or overlapping at certain sizes.
Then test accessibility. Navigate the whole site using only the Tab, Enter and Escape keys and make sure the focus is always visible. Check that every image has suitable alt text, headings form a sensible outline and text meets contrast guidelines. Lighthouse includes an automated accessibility check, but it cannot catch everything, so manual testing still matters.
Finally, check the details. Click every link, submit every form with both good and bad data, and confirm error and success messages appear. Visit an address that does not exist to see your 404 page. View each page's title and description, run Lighthouse for performance, and fix the most important issues. Keep the checklist, as it is useful after every future update too.