What is Emailens used for?

Emailens is an email rendering linter that checks HTML emails across 21 clients including Gmail, Outlook and Apple Mail, from the editor, CLI, CI or an AI assistant. It is a good fit for catching Outlook rendering bugs before sending, running email checks in CI pipelines and generating tested emails from a prompt.

Yes. Emailens has a free plan, and paid plans start at $9 per month.

Is Emailens open source?

No. Emailens is proprietary (closed-source) software. In the Testing & QA category, open-source options include pytest-testmon, k6 and Tox.

Can I self-host Emailens?

Yes. Although Emailens is closed source, it can be self-hosted on your own servers, and the vendor also offers a hosted version.

What are some alternatives to Emailens?

Emailens competes with Litmus and Mailtrap.

Emailens: features, pricing and alternatives

About Emailens

Emailens finds the parts of an email that break in different inbox clients before it is sent. It reads the email source and reports problems, such as unsupported CSS properties or invalid Outlook VML, for 21 clients including Gmail, Outlook Classic and New Outlook, Apple Mail, Yahoo and Samsung, with fix snippets written for React Email, MJML and Maizzle.

It runs where developers already work: a CLI, a GitHub Actions step, an MCP server for Claude and Cursor, a REST API, a Figma plugin and a Chrome extension. An AI Builder generates emails in React Email, MJML, Maizzle or plain HTML and repairs its own output across the supported clients, and an AI Fix feature turns compatibility warnings into patches.

The core engine is open source and the product is free to start, with Dev and Pro plans that raise the AI Builder allowance. It sits between building and shipping rather than replacing the email framework, and the site also offers free HTML email templates, free developer utilities and a CSS support table for the 21 clients.

Key features

Linting of email HTML for 21 clients
Fix snippets for React Email, MJML and Maizzle
CLI and GitHub Actions for CI checks
MCP server for Claude and Cursor
AI Builder that generates and self-repairs emails
Figma plugin and Chrome extension
Free email templates and CSS support table

Good fit for

Catching Outlook rendering bugs before sending
Running email checks in CI pipelines
Generating tested emails from a prompt

Tags: email; email-testing; linter; react-email; mjml; maizzle; developer-tools; ci

Emailens: questions and answers

What is Emailens used for?: Emailens is an email rendering linter that checks HTML emails across 21 clients including Gmail, Outlook and Apple Mail, from the editor, CLI, CI or an AI assistant. It is a good fit for catching Outlook rendering bugs before sending, running email checks in CI pipelines and generating tested emails from a prompt.
Is Emailens free?: Yes. Emailens has a free plan, and paid plans start at $9 per month.
Is Emailens open source?: No. Emailens is proprietary (closed-source) software. In the Testing & QA category, open-source options include pytest-testmon, k6 and Tox.
Can I self-host Emailens?: Yes. Although Emailens is closed source, it can be self-hosted on your own servers, and the vendor also offers a hosted version.
What are some alternatives to Emailens?: Emailens competes with Litmus and Mailtrap.