How to Convert MJML to HTML Online
How do you convert MJML to HTML online?
Paste your MJML into MailViewr, which compiles it to responsive, Outlook-safe HTML in the browser. Preview the result across Gmail, Outlook, Apple Mail and mobile, then download the generated HTML — free, with 5 free previews before signup, no install required.
MJML lets you write compact, component-based email markup that compiles into battle-tested HTML. Here's the fastest way to convert MJML to HTML online — and, just as importantly, to confirm the output actually renders the way you expect.
Convert MJML to HTML in four steps
- Paste your MJML into the MJML to HTML converter.
- Compile in-browser — MailViewr runs the official MJML engine client-side.
- Preview & QA the generated HTML across Gmail, Outlook, Apple Mail and mobile.
- Download the HTML and use it in any ESP.
Have an HTML email already? Paste it in and see exactly how it renders across Gmail, Outlook, and mobile — before you send.
Test My HTMLDon't have one built yet? Start in the builder
Why not just use the MJML CLI?
The CLI works, but it needs Node installed and gives you only HTML — no preview. An online converter that also previews and tests the output saves the round-trip of compiling locally, pasting into a separate previewer, and guessing about Outlook. With MailViewr you compile, preview, run a QA report, and download — in one place.
From converter to verified send
Converting is step one. If you want to see how the result renders before you ship it, use the MJML email preview tool to check Gmail, Outlook, Apple Mail, mobile and dark mode against the compiled HTML.
Have an HTML email already? Paste it in and see exactly how it renders across Gmail, Outlook, and mobile — before you send.
Test My HTMLDon't have one built yet? Start in the builder