MJML App

Free and open source · MJML 5

Write responsive emails.
See them as you type.

MJML App is a desktop editor for MJML. Write the markup on the left, and the email renders on the right in milliseconds. Import a Figma design, send a test email and export clean HTML, all from one window.

Download View on GitHub

macOS · Windows · Linux

The MJML App editor: MJML code on the left, the rendered email on the right

Features

Everything you need to ship an email

From the first tag to the test in your inbox, without a browser tab or a build step.

Live preview

The email renders as you type. Switch between the desktop and mobile widths, and see the render time in the status bar.

A real code editor

CodeMirror 6 with MJML autocompletion for tags and attributes. MJML errors show in the gutter, next to the line.

Figma import with AI

Select a frame in Figma and get MJML back. Then ask the AI to refine it. Use your own key for Claude, OpenAI or Gemini, or a local model with Ollama.

Test emails

Send the email to your inbox with your Mailjet account, and check it in real email clients before you ship.

Templating

Preview Handlebars or ERB templates with variables in YAML or JSON. Each project keeps its own variables.

HTML export

Export minified or readable HTML. The app copies the local images that the email uses, and never overwrites a file.

Partials

Split a long email into headers and footers with mj-include. A partial file shows its own preview.

Light and dark

A native look on each platform, with a light and a dark theme that follow your system.

MJML 5 built in

The app comes with MJML 5. You can also point it to your own mjml binary and .mjmlconfig file.

From design to code

Turn a Figma frame into MJML

The app reads the frame from the Figma desktop app or the Figma API, downloads the images to your project and sends the design to the AI model you choose.

  • The result is validated with MJML, and the errors go back to the model
  • A visual check compares a screenshot of the result with the design
  • Your API keys stay encrypted on your computer

Projects

All your emails in one place

Open a folder and it becomes a project. The list shows a thumbnail of each email, and you can sort, rename and duplicate them. Double-click a .mjml file to open it in the app.

The project list of MJML App, with a thumbnail of each email

Download

Get MJML App

Free for macOS, Windows and Linux. See what is new.

The first launch

The installers are not signed, so macOS and Windows show a warning the first time you open the app.

macOS

Move MJML to Applications, then run this command in Terminal:

xattr -dr com.apple.quarantine /Applications/MJML.app

Or open the app, then go to System Settings › Privacy & Security and click “Open Anyway”.

Windows

When SmartScreen shows “Windows protected your PC”, click “More info”, then “Run anyway”.

Updates

On Windows and Linux (AppImage), the app updates itself. On macOS, download the new .dmg from this page.

Build it yourself

You need Node.js 24 and Yarn 1. Contributions are welcome.

$ git clone https://github.com/ahmetkorkmaz3/mjml-app.git
$ cd mjml-app && yarn
$ yarn dev