Read Time: 5 min

Now available in Litmus Email Previews: Terra

Update: Terra retiring its free email service
On June 30, 2017, Terra retired its free Terra Mail service and discontinued support for email addresses with the domains,,,,,,, and
Litmus retired Email Previews for Terra as of July 1, 2017.

We’re excited to announce our most recent addition to Litmus Email Previews: Terra. Owned by the Spanish corporation Terra Networks, and with a presence in Spain and many countries in Central and South America, Terra’s free email service is popular among Spanish-speaking audiences.

Compared to other webmail clients, Terra provides very limited support for HTML and CSS. If you haven’t yet considered how your email looks in Terra, chances are your campaigns may look broken in this client.

Optimize your email for International inboxes

Test your email in popular international webmail clients, including Terra, with Litmus Instant Email Previews—and catch rendering errors before you send.

Test your email →


Don’t have access to a Terra account to test your design? With Litmus Email Previews, you can instantly see how your email looks like in Terra’s inbox, so you can quickly identify and fix issues before you send.

Plus, to make building emails that look great in Terra even easier for you, we’ve taken a close look at the client and its support for basic and more advanced HTML and CSS. Here’s what we found.

See an example email in 70+ clients, including Terra →
See an example email in 70+ clients, including Terra →

The Inbox View

Visible subject line length

depends on browser window size

Emoji support in subject line


Preview text support


Visible preview text length


Visible from name length

21 characters

Auto sorting (folders or tabs)



Message View

Preview pane support


Width of window for email


Length of email (Is it clipped?)



Quirks to Note

Ensure images don’t exceed 700px in width

While Terra’s preview window is 740px wide, additional padding within the preview pane can lead to an unintended need for horizontal scrolling. This happens whenever an email contains an image that is wider than 700px. Keep your images below that maximum width to make sure your subscribers don’t have to scroll sideways to see the full content of your email.

Are your subscribers opening on Terra?

Dive into detailed email analytics and learn what email clients your subscribers use to open your email, with Litmus Email Analytics.

Get to know your audience →


HTML and CSS Support

The Basics

Style support in head


Media query support


CSS attribute selector support






Images and Visuals

Images enabled by default?


Animated GIF support


ALT text support


Styled ALT text support


Background images support


HTML5 video support














Web fonts


Progressive Enhancement

Border Radius


Interactivity — checkbox/ radio button support


Animation — transitions/keyframe animation support



Terra’s limited support for HTML and CSS, including the lack of support for media queries and style tags in the email header, can be a challenge for email marketers. Here’s how to make sure your email still renders correctly:

    • Inline your CSS
      “Inlining” styles moves the CSS and associated formatting instructions from the style block in the head of your email into the body of the HTML. While doing this manually can be a tedious process and is prone to mistakes, there are ways to automate this step. Try our CSS Inliner in Litmus Builder and inline your styles in just seconds.
    • Use hybrid coding techniques
      Hybrid coding is a flexible coding technique that doesn’t rely on media queries to resize and change the email width for different device sizes—a perfect approach to cater to clients that don’t support media queries (like Terra) but still ensure your email looks great on mobile, too.
    • Embrace the power of the animated GIF
      With no support for HTML5 video, the best way to add some motion to your email is through animated GIFs.

Enabling Terra Email Previews in Litmus

Litmus allows you to test your email in more than 70 clients and devices. To help streamline your testing efforts, you can enable those clients that are important to you (or remove clients that aren’t important for your audience). To add Terra to your default clients for testing, head over to the account settings in your Litmus account and choose “configure clients”. Check the box next to Terra (and any other client you’d like to add to your default settings) and click save. Your selected email clients are now the default for all Email Previews in Litmus Checklist and Builder.

We’d love to hear from you

Did you discover a rendering quirk in Terra that we missed? Struggling with a code question specific to Terra’s web client? Let us know in Community!

Start a discussion →