How to validate links and images before sending?

Link validation should verify that every URL returns a successful response (HTTP 200) and lands on the intended destination. Most rendering tools include automated link checkers that crawl your email and flag broken URLs, redirects to unexpected destinations, or links to blocklisted domains. For personalized or dynamic URLs, test with multiple subscriber profiles to ensure all variations resolve correctly.

Image validation confirms that all images load from their hosted locations and display at expected dimensions. Check that image URLs use HTTPS (HTTP images may be blocked or show warnings), that file sizes are optimized for fast loading, and that every image includes appropriate ALT text. Preview your email with images disabled to verify it remains functional and comprehensible. This uis how many recipients first see your email.

Beyond technical validation, click through every link manually at least once before major sends. Automated tools verify that links work; manual testing verifies they work correctly. That utracking parameters are present, that landing pages match campaign messaging, that mobile links don't lead to desktop-only experiences. A single broken link or missing image is a credibility wound; systematic validation prevents the careless errors that erode subscriber trust.