free tool

HTML Email Tester

Paste HTML, preview it live, and send a real test message through Mailgun. Ideal for checking transactional templates, CTA buttons, and plain-text fallbacks before you ship.

Live preview

How the HTML email tester works

Your markup is sanitized (scripts and inline event handlers stripped), rendered in a sandboxed preview, and queued through our Mailgun sending domain. Use it to verify layout, links, and subject lines against real inbox rendering — Gmail, Outlook, and mobile clients each interpret HTML slightly differently.

Free-tier limits

Sends are rate limited per IP and share a daily budget so the tool stays free for everyone. If the quota message appears, try again after the UTC day rolls over or send from another network.