Litmus

Litmus specializes in email testing, previewing, and analytics, helping marketers ensure consistent rendering across dozens of email clients and devices. Teams can use Litmus Builder to code responsive templates with real-time previews. A QA checklist scans for broken links, missing images, and spam-filter triggers. Campaigns can be tested in Outlook, Gmail, Yahoo Mail, and more before sending. Integrations with ESPs like Salesforce Marketing Cloud or Mailchimp streamline workflows. Post-send analytics track engagement, forward rates, and read time, guiding iterative improvements for top-tier email performance.