Overview

As a marketing operations leader or a dedicated email marketer, you understand the constant pressure to deliver campaigns that not only look great but also perform exceptionally. In an increasingly crowded inbox, achieving true email excellence isn’t just about crafting compelling copy and eye-catching designs; it’s about ensuring your emails land perfectly, render flawlessly, and resonate powerfully with every recipient. This is where a platform like Litmus becomes not just a helpful tool, but an indispensable strategic asset.

Having navigated the complexities of email marketing for years, we’ve seen firsthand the transformative impact that a robust email optimization platform like Litmus can have. In this post we’ll dive deep into what Litmus is, why it’s become a cornerstone for high-performing marketing teams, and how it can elevate your campaigns from good to truly great. 

What is Litmus?

At its core, Litmus is a comprehensive email marketing platform designed to empower teams to build, test, and analyze email campaigns with unparalleled precision. Think of it as your all-in-one quality assurance and optimization hub for every email that leaves your organization. It’s not an email service provider (ESP) itself, but rather a powerful complement that can supercharge your email workflow.

Key functionalities within Litmus include:

• Email Previews & Testing: This is the most well-known feature. Litmus provides instant previews of your email across dozens of email clients, devices, and dark mode settings. No more guessing how your email will look in Outlook 2016, Gmail on an iPhone, or Apple Mail in dark mode – you’ll know for certain.
• Spam Testing: Before your email even hits an inbox, Litmus helps you identify potential red flags that could trigger spam filters, ensuring deliverability.
• Code Editor & Builder: For those who prefer to build or refine their emails directly, Litmus offers a robust code editor with live previews and real-time error checking. It also features a visual builder for faster, more intuitive creation.
• Collaboration & Workflow: Streamline your review and approval processes with commenting, task assignment, and version control, keeping your entire team on the same page.
• Analytics & Insights: Beyond pre-send testing, Litmus provides post-send analytics, offering insights into how your emails are performing, including engagement rates and reading environments.
• Accessibility Checks: Ensure your emails are inclusive and accessible to all recipients, including those using screen readers, by identifying potential accessibility issues.

In essence, Litmus de-risks your email campaigns by providing an objective, real-world view of how your emails will perform before they ever reach a recipient’s inbox.

Why Use Litmus? The Imperative for Email Excellence 

In today’s competitive landscape, the “why” behind adopting a platform like Litmus is rooted in tangible business benefits that directly impact your bottom line. It’s not just about aesthetics; it’s about effectiveness too. 

• Protecting Brand Reputation: Sending a broken, poorly rendered, or spam-flagged email decreases trust and damages your brand. Litmus acts as a guard rail, ensuring every email reflects the quality and professionalism your brand stands for.
• Maximizing ROI on Email Marketing: Email consistently delivers one of the highest ROIs in marketing. However, that ROI is contingent on how well your emails are actually performing. By optimizing rendering, deliverability, and engagement, Litmus helps you craft the most effective content. 
• Ensuring Consistency Across Diverse Audiences: Your audience uses a myriad of devices and email clients. Litmus ensures that your carefully crafted message looks and functions consistently for everyone, eliminating frustrating user experiences.
• Improving Key Performance Indicators (KPIs): Flawless rendering, higher deliverability, and engaging experiences directly translate to:
  • Increased Open Rates: Emails that look professional and land in the inbox, and therefore not marked spam, are more likely to be opened.
  • Higher Click-Through Rates (CTRs): When your email renders as intended and the content is easily consumable, users are more likely to engage with your calls to action.
  • Enhanced Conversion Rates: Ultimately, better engagement leads to more conversions, whether that’s a purchase, a download, or a sign-up.
  • Lower Unsubscribe Rates: A positive email experience contributes to subscriber satisfaction, reducing churn.

How to Use Litmus: A Beginner’s Step-by-Step Guide

Getting started with Litmus is pretty straightforward because of its intuitive interface. While the platform offers advanced features, the core testing process is simple yet impactful. Below are the basic steps you’ll take when testing out an email through Litmus. 

Step 1: Get Your Email into Litmus

• Send a Test Email to Your Litmus Address: This is often the most common method. Litmus provides a unique email address for your account, so this is where you’ll send your test email. Litmus then automatically processes the email and generates the previews and reports.
• Paste HTML Code: If you’re building your emails directly in an HTML editor, you can copy and paste the HTML code into Litmus. This is quick for a rapid check of your code.
• Upload an HTML File: For more complex emails with external assets, you can upload your HTML file along with any referenced images, stylesheets, or other files as a .zip archive.

• Use Litmus Builder (If Applicable): If your Litmus plan includes Litmus Builder, you can directly build or import your email within the platform. Any changes you make are instantly reflected in the previews.

Step 2: Navigate to the Previews & QA Tab

Once your email is processed, click on it and go to the “Previews & QA” tab. This is where you’ll see how your email renders across various email service providers along with multiple versions of each provider. 

• See Client Previews: Click on any of these to see a full-size screenshot of how your email renders in that specific platform.

• Identify Visual Glitches: Scroll through the previews. Pay close attention to how your email looks across a variety of email providers and applications:
  • Broken Layouts: Do columns collapse incorrectly? Are images overflowing?
  • Font Rendering: Do your chosen fonts display as intended? Are they legible?
  • Image Display: Are all images loading? Are they the correct size? Do they have alt text (alternative text for accessibility)?
  • Dark Mode Issues: Are your colors inverting correctly? Is text becoming unreadable against dark backgrounds?

Litmus has 2 main plans: Litmus Core and Litmus Enterprise. Additionally, there’s the Deliverability add-on plan that incorporates some extra features such as an inbox placement insights by mailbox provider, 24/7 reputation and deliverability monitoring, and visibility into competitors’ sending practices, and more. These plans can be accessed on the Litmus pricing page. 

Litmus can provide previews on 120+ client and device options all at once. From these options, you can choose as many or as little as you like to preview.

Within these many options includes popular providers on various platforms such as:

Webmail: Gmail, Outlook, Yahoo, Office 365, AOL Mail, G Suite

Desktop clients: Outlook, Apple Mail, Thunderbird

Mobile apps: Gmail app (Android, iOS), Outlook app (Android, iOS), Samsung Mail

Mail on various iPhone/iPad devices (with light/dark mode previews)

While Litmus encompasses nearly all major email providers in use on a global scale, it doesn’t include every obscure or rarely used email application. However, Litmus adds new clients regularly under its ‘New & Recently Updated’ list which makes an effort to account for new applications or devices in use on an ongoing basis. Litmus’ wide range of previews amongst the most popular email providers and applications allow marketers to feel confident that the vast majority of their recipients will receive emails that display and function as intended. 

 Step 3: Leverage the QA Checklist

Beyond visual previews, Litmus provides an automated QA checklist that flags common issues:

• Link Validation: Litmus automatically checks all links in your email to ensure they are valid and not broken.
• Image Optimization: It can identify images without alt text, which is crucial for accessibility, and flag oversized images that might slow down load times.
• Tracking Validation: If you use tracking pixels or codes, Litmus can help confirm they are properly implemented.
• Accessibility Checks: Look for warnings related to color contrast, text size, and other accessibility best practices that can make your emails usable for everyone.

Step 4: Run a Spam Test

In the “Spam Testing” tab you can identify potential issues that could impact your deliverability rates. Select the ‘Test your email’ button dropdown on either the Home or Emails page, then select ‘Start a spam test’.

Once you select ‘Start a spam test’, you’ll see two different options, ‘Pull from your ESP’ and ‘Manual Send’.

Pull from your ESP

You’ll need to have an existing ESP integration for this option. Once that integration is set up, spam testing starts with the same ‘Start a new Spam Test’ button.

Select ‘Pull from your ESP’, choose your ESP and an email, and then the ‘Start your test’ button. The test results Summary window will appear as your results begin to process.

Manual send

This option provides a unique list of email seed addresses for each test. Use all the addresses that are populated in the list and send your email from your ESP. 

If your ESP allows importing addresses, you can click the ‘Download CSV’ button to download a copy. Otherwise, click the ‘Copy to clipboard’ button to copy the list and paste the addresses in to send.

Once you’ve sent the email to your seed entire list, click on the ‘Yes, I’ve sent it’ button to start receiving your results.

Spam test results

Spam test results are categorized by Authentication Filters, Blocklist Filters, Placement Filters, and Score Filters. Click on ‘Results’ on the left hand side to see the detailed list for each test. All results will provide additional information about the specific check and how it can be troubleshooted.

Spam results in Previews & QA checklist

If you build in Litmus, you’ll find a spam check email address to send in your email for essential checks results.

When you send in a draft email, the essential spam checks will appear in the Spam Testing section of your Previews & QA.

Step 5: Collaborate and Get Approvals (Using Litmus Proof)

If your team uses Litmus Proof, this is where the collaboration happens:

• Share for Review: Generate a shareable link for your email proof.
• Collect Feedback: Team members and stakeholders can add comments and annotations directly on the email previews, making feedback clear and contextual.
• Track Progress: You can see who has reviewed the email, what feedback has been given, and mark comments as resolved.

Step 6: Make Revisions and Retest

Based on the insights from your previews, QA checks, and spam tests, go back to your email creation platform (your ESP, HTML editor, or Litmus Builder) and make the necessary adjustments. Once revisions are made, send another test to your Litmus address to see the updated previews and ensure all issues are resolved. 

Following these steps can help ensure your emails are designed optimally across a variety of platforms and have any potential deliverability issues kept to a minimum. 

How Can Litmus Improve Your Marketing Campaigns?

1. Pre-Deployment QA and Troubleshooting

Before any campaign goes live, your team can:

• Catch Rendering Issues: Instantly identify broken layouts, font rendering problems, image display issues, or responsive design glitches across various email clients (Outlook, Gmail, Apple Mail, mobile apps, etc.) and devices (iOS, Android, desktop).
• Validate Links & CTAs: Ensure all links are functional and directing properly.
• Optimize for Dark Mode: Litmus shows exactly how your email will appear in dark mode, allowing you to optimize colors and images to prevent readability issues or unexpected visual distortions.
• Preview Personalization: If you’re using dynamic content or personalization tags, you can see how these will render with actual data.

2. Enhancing Deliverability

Getting your email into the inbox is half the battle. Litmus equips you with tools to successfully do this by:

• Spam Testing & Analysis: Run your email through a variety of spam filters (like SpamAssassin) and receive a detailed report on potential red flags, such as suspicious keywords, formatting issues, or sender reputation problems. This allows you to proactively adjust your content and coding to improve deliverability.
• Sender Reputation Monitoring: While not a direct Litmus feature, understanding how your emails are perceived by internet service providers is critical. Litmus testing can indirectly inform your strategy by identifying potential issues that could negatively impact your sender score.

3. Streamlining Collaboration and Workflow

Email campaign creation often involves multiple stakeholders – designers, copywriters, developers, and approvers. Litmus facilitates efficient teamwork because of the following:

• Centralized Review & Feedback: Teams can leave comments directly on specific parts of the email preview, assign tasks, and track revisions within the platform.
• Version Control: Easily compare different versions of an email to track changes, ensuring everyone is working from the most current iteration.
• Brand Consistency: Use Litmus’s design system capabilities to maintain consistent branding, fonts, and styling across all your email communications, reinforcing your brand identity.

4. Post-Send Optimization & Learning

Litmus provides valuable insights for continuous improvement post deployment:

• Email Client Usage Analytics: Understand which email clients and devices your audience is using to read your emails. This data is invaluable for prioritizing your testing efforts and tailoring future designs.
• Engagement Tracking: Go beyond basic open and click rates to see how long recipients are reading your emails (glanced, skimmed, or read), providing a deeper understanding of content effectiveness.
• A/B Testing Insights: While Litmus doesn’t directly run A/B tests, its pre-send capabilities allow you to confidently test different email variations (like subject lines, preheaders, layouts, CTAs, etc.) knowing they will render correctly, giving you cleaner data for your A/B test analysis.

Coding Guidelines for Consistent Rendering

Email platforms vary how certain bits of code will render in each email. For example, MS Outlook is often the most challenging platform for marketers as some versions, both older and newer, use Microsoft Word’s rendering engine, which has very limited support for modern CSS. Common coding issues and potential solutions for this platform specifically can be in these two articles: Outlook HTML Emails: How to Fix 11 Common Rendering Issues and How to Code Perfect Emails for Outlook: Avoiding Common Pitfalls. However, following the general guidelines below is a good start for the vast majority of emails you build.

• Use Tables for Layout – Unlike web design, where div elements are the standard for layout, email rendering is most consistent when you use nested tables for your structure. This old-school approach is a reliable way to control the layout and prevent elements from breaking, especially in older versions of Outlook.

Example: <table width=”600″ cellpadding=”0″ cellspacing=”0″ border=”0″ align=”center” style=”border-collapse:collapse;”> <tr> <td width=”300″ valign=”top”> <p>This is the left column.</p> </td> <td width=”300″ valign=”top”> <p>This is the right column.</p> </td> </tr> </table>

• Inline Your CSS – Many email clients, including Gmail and some versions of Outlook, strip out CSS defined in the <head> section. To prevent your styles from being lost, you must inline your CSS. This means applying styles directly to each HTML element using the style attribute.

Example: <h1 style=”color:#FFFFFF; background-color:#000000; font-size:24px;”>Hello World</h1>

• Embrace Responsive Design – Many people read emails on their phones so this must be taken into consideration with each email design. Use CSS media queries to create breakpoints that adjust the layout for different screen sizes. These media queries should be placed in the <head> of your email, as they are generally supported by most modern email clients. The code below changes a two-column layout to a single-column layout on screens smaller than 600 px (i.e. mobile devices). 

Example: <head> <style type=”text/css”> @media screen and (max-width: 600px) { .column { width: 100% !important; display: block !important; } } </style> </head> <body> <table width=”100%” cellpadding=”0″ cellspacing=”0″ border=”0″> <tr> <td class=”column” style=”width:50%;”> </td> <td class=”column” style=”width:50%;”> </td> </tr> </table> </body>

• Target Outlook Specifically – Outlook for Windows uses Microsoft Word’s rendering engine, which often requires special coding. You can use Conditional HTML (often referred to as MSO conditional code) to create specific code blocks that are only visible to Outlook. This allows you to serve a simplified or modified layout to Outlook users without affecting the rendering in other clients.

Example: <a href=”http://www.example.com” style=”background-color:#007bff;border-radius:5px;color:#ffffff;display:inline-block;font-family:sans-serif;font-size:16px;font-weight:bold;line-height:40px;text-align:center;text-decoration:none;width:200px;-webkit-text-size-adjust:none;mso-hide:all;“>Click Here</a>

• Optimize Images and Alt Text – Always specify the width and height attributes for images in your HTML to prevent them from breaking the layout if they don’t load. Also, use descriptive alt text for all images, as many email clients block images by default. This ensures the recipient still understands the message even if the images are not displayed.

Example: <img src=”https://www.example.com/image.jpg” alt=”A smiling team of employees working in an office.” width=”400″ height=”200″ style=”display:block; border:0;”>

Conclusion

In the dynamic world of digital marketing, email remains a powerful channel. However, its effectiveness is directly proportional to the quality and consistency of your execution. By mitigating risks, streamlining workflows, and providing invaluable insights, Litmus empowers marketers to consistently deliver emails that not only reach the inbox, but are more likely to perform better overall. 

For marketing operations teams striving for high performing campaigns, using a tool like Litmus is worth the investment. If you’re interested in learning how we at Etumos utilize Litmus to its full potential to accelerate Campaign Operations or simply want to learn more about the platform, contact us.