The only code editor built specifically for email

Build, edit, and preview your emails across 70+ clients in real time

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Build the perfect email

Build your email in our web-based editor and get instant previews in over 70+ email clients as you go. Every change you make updates your previews in real time, so you can build, test, and troubleshoot faster than ever before.

Email client 1
Apple Mail 8
Email client 2
Apple Mail 9
Email client 3
Email client 4
Outlook 2000
Email client 5
Outlook 2003
Email client 6
Outlook 2013

Instant previews

Get instant previews of your email in 70+ email clients as you're building. See your design in both mobile and desktop dimensions, ensuring compatibility across environments.


See code changes in real time

Every change updates your previews in real time. No more switching between your code editor and ESP—or manually checking five separate devices—every time you make a change to your email.

Template 1
Template 2
Template 3
Template 4
Template 5
Coupon Sale
Template 6
Event Invitation


Build your email from scratch, or create your own template. You can also choose from one of our pre-tested and customizable templates that work everywhere.

Grid view

Grid view

Easily navigate your code—click on any HTML element in the preview pane and land on that element directly within the code editor.

Cut your development time in half

Designing email doesn’t have to be so frustrating.

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CSS inlining

Automatically inline your email’s CSS with a simple toggle and style your emails faster and easier than ever before.

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Avoid repeating yourself by creating reusable snippets for commonly used elements, like bulletproof buttons and preheader text.

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View your entire email’s history. See who made changes and when and easily restore any version at any time.

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Create a public version of your email to share with others or embed on any site with a single click.

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Images on and off views

Toggle images on and off to see ALT text, optimize your email for image blocking, and ensure your CTA is visible.

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Responsive views

Ensure that your email is easy to interact with in all environments by viewing it in both mobile and desktop.

Coupon Sale
Event Invitation

Builder for Designers

Save time

Cut your development time in half by no longer having to test and troubleshoot locally on five different devices.

Quality templates

Browse our gallery of pre-tested templates that look great and work everywhere.

Automate tasks

Easily automate tasks out of the box like CSS inlining or sending test emails.

Litmus for Designers
Builder split view

Builder for Marketers

Instant Previews

Optimize every send by previewing your email in 70+ apps and devices before you press send.

Quality templates

Browse our gallery of pre-tested templates that look great and work everywhere.

Responsive design

Improve your performance everywhere by viewing your email in both mobile and desktop dimensions before sending.

Litmus for Marketers

Builder for Agencies

Keep projects on track

Save project time and cost by having each of your design and development teams testing and iterating on real email clients, right in Litmus Builder.

Quality templates

Create consistent templates and branding across your team with a saved template library and saved code snippets that can be shared across your development teams.

Share projects internally

Use Builder’s built-in sharing features to share projects collaboratively amongst your internal teams and to your clients for review and feedback.

Litmus for Agencies