MJML Email Builder

MJML Email Builder

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What is MJML Email Builder

MJML Email Builder is a free browser tool for writing MJML email templates, compiling them in the browser for preview and checks, and sending a test through your own Mailpit-compatible HTTPS endpoint.

Download saves the MJML source (email-template.mjml). Preview, Check email, and Send test use the compiled HTML. There is no separate “Get HTML” download in the UI — keep MJML as source of truth, or copy compiled output from preview workflows as needed.

Client-style previews are simulations, not native inbox engines. Compilation uses the tool’s in-browser MJML runtime.

How to use MJML Email Builder

  1. Step 1: Load MJML. Paste MJML or Import .mjml / .html / .eml / .mime (or start from Templates).
  2. Step 2: Preview compiled output. Edit MJML and review client-style layouts, light/dark, and desktop/mobile form factors.
  3. Step 3: Clean up and personalize. Use Format, Inline CSS, or Minify on the source when needed. Open Payload for {{ variables }}.
  4. Step 4: Check, download MJML, or send a test. Run Check email, Download email-template.mjml, or Send test to your Mailpit HTTPS Base URL.

MJML Email Builder Features

  • MJML editor with in-browser compile for preview
  • Import .mjml, .html, .eml, and .mime
  • Format, Inline CSS, and Minify on the source
  • Templates gallery and Payload JSON for merge tags
  • Send test via your Mailpit-compatible HTTPS Base URL
  • Check email tabs (HTML, source, text, headers, QA, HTML Check, Link Check)
  • Download as email-template.mjml
  • Client-style previews with light/dark and desktop/mobile

Common use cases

  • Draft responsive emails in MJML: Build column layouts and components in MJML without a local Node toolchain for everyday editing.
  • Preview before handoff: Review compiled HTML in client-style sims, then download MJML for your repo or ESP workflow.
  • Merge-tag proofs: Fill Payload JSON and confirm personalized regions in preview.
  • QA and link checks: Use Check email before you push a template to production.
  • Mailpit send test: Deliver a compiled test to Mailpit behind HTTPS when you want a real message in a mailbox you control.

Examples / supported formats

MJML Email Builder focuses on MJML source and compiled preview:

  • MJML in the editor
  • Import: .mjml, .html, .eml, .mime
  • Download: email-template.mjml (editor source)
  • Compiled HTML used for preview, checks, and Send test
  • Payload JSON for {{ variable }} previews

Prefer raw HTML email? Use HTML Email Builder. Snapshot tools: HTML to PNG, HTML to JPG, HTML to PDF. Mailpit + ngrok guide.

FAQ

Is MJML Email Builder free?
Yes. Tools Viewer tools are free to use in the browser with no account required.
Do I need to create an account to use MJML Email Builder?
No. Open the tool and start working — signup is not required.
Where is MJML compiled?
Compilation runs in your browser with the tool’s MJML runtime. Keep secrets out of any template you paste into an online editor.
Does Download give me compiled HTML?
No. Download saves the MJML source as email-template.mjml. Preview and Send test use the compiled HTML. For HTML screenshots or PDF snapshots, use HTML to PNG, HTML to JPG, or HTML to PDF.
How is this different from HTML Email Builder?
This tool locks the editor to MJML. HTML Email Builder locks the editor to HTML. Both share preview, checks, Payload, and Send test patterns.
What is MJML?
MJML is a markup language that compiles to responsive HTML email. You write higher-level layout components; the compiler emits table-based HTML many email clients understand.