Coding, adapting, and adapting again — it's a pain. But there's good news: the tools that make email testing much easier are right at your fingertips. Let us make things easier and share information about services with built-in tools for efficient work: Email on Acid, Litmus, Testi@, and others.

Popular services with automatic email checking

Let's go back in time. To check an email across different clients even 10 years ago, you had to do a ton of extra work and use a bunch of different sites. Register company accounts on every existing email platform, open them, and test every email by hand. Doesn't sound great, does it?Checking email is much simpler now. You choose a convenient platform, test your email across different browsers and apps, review the rendering, and draw your conclusions. With these helpers, a full check has become much faster and easier. Here are the most popular ones:

  • Litmus
  • Email on Acid
  • Testi@
  • Mail Tester
  • EmailPreviewServices
  • Htmlemailcheck.com
  • Google AMP Playground

Before we get into how great they are, let's be clear: quirks and bugs exist everywhere. Try out a few services, get familiar with their interfaces, and then pick the favorite you'll actually use.

Let's briefly walk through the capabilities of the first three platforms and figure out how to work with them.

Litmus

One of the most popular web services around. Functionality, updates, and presentation are what push email coders and email marketers to use Litmus. On the site, experts run a blog and produce video content.

Litmus brings together all the tools you'll need in your work. Test and adapt your emails for different email clients and browsers.

Checking and testing in Litmus: what it is and how it works

Layout testing means checking an email template across 70+ email clients and devices. In Litmus, the process takes a couple of seconds. The system checks the uploaded template and flags errors:— Flags broken links— Finds images without alt text— Adapts the template for different browsersTesting in Litmus can be described in 4 steps. Follow each one, and you'll have the Litmus test figured out:

  1. Open the Litmus test, pick a template, and launch the check.
  2. The platform automatically adapts the email for all email clients. By the way, the tests run on real devices, not emulators.
  3. Wait a couple of seconds — during that time, the program takes screenshots of all the results.
  4. Log into your dashboard and review the results.

As for drawbacks: in many cases Litmus ignores errors and returns a passing result. The system says everything's "fine," while in reality the emails aren't rendering correctly.

The service also has other tools: Litmus Builder, Subject Line Checker, and Spam Test.

Email on Acid

A Litmus alternative that includes everything you need to check emails. Its main tools: Testing, an HTML Editor, and a Spam Tester.

There's even a blog with useful articles on coding, design, and AI. Plus a library of ready-made templates, accessible even on the basic plan.

In terms of capabilities: you can test emails across 70+ email clients and devices. As for rendering: everything works as expected. Information and the list of supported email clients are on Email on Acid's official website.

As for the downsides: the service isn't a great fit for ongoing, frequent checks. If you have one or a few small emails, then sure. If not, it's better to look for an alternative. And one more thing: there aren't many Android devices for testing here.

Campaign Precheck: a testing tool

Email on Acid has a separate tool for checking templates. It includes a test, coding tips, and results. The service is convenient for users, but access is only available with a paid subscription.

A quick rundown of the features:

  • Email accessibility scoring
  • Header preview (preheader and subject line)
  • Image scanning with the ability to set a fixed size
  • URL correctness analysis

There's a free 7-day trial. After that, a daily plan with unlimited tests.

Testi@

The platform supports 60+ email clients. You can upload a template several ways: as an archive, via HTML, or through a test email address.

You run the check, and the code appears on screen. On the right side of the screen, errors that need fixing are highlighted and listed. You can only see what this looks like with a paid subscription.

As for the downsides: not many tools and email clients — on the free plan you can only test with Gmail and Yahoo. Though the paid plans are reasonably priced.

Conclusions

Yes, working with email campaigns is hard. Special services can handle coding, testing, and checking for you — get to know them, explore their features. These services let you adapt templates for email clients, find errors faster, and fix them.In Letteros you can test how emails render on 50+ devices and email clients.