Resources Hub » Knowledge base » Can You Use CSS In HTML Emails?

Your branding and content should look perfect on every device in every email campaign. That’s simply table stakes when it comes to marketing content and putting your brand in the best light possible.

And an ESP should make this easy. In this modern era of marketing technology, you shouldn’t need vast coding knowledge to make an email campaign look the way you envision. Does it help? For sure. But should you be able to send incredible campaigns without employing your own CSS? Definitely.

Can you use CSS in HTML emails?

The short answer here is yes, you can use CSS in traditional HTML emails. You just need to follow a few basic guidelines. At this point, users are typically split between Gmail and Apple iPhone email clients. Gmail and iPhone each hold 29% and 28% of the email client market, respectively. Keep in mind: This could change depending on your specific audience, especially whether you’re a B2C or B2B company.

Apple and Gmail comprise nearly 60% of the email client market share.

Back to it: the CSS guidelines you need to follow.

Use a drag-and-drop builder.

A drag-and-drop builder will help ensure that your emails always look perfect on every device and email client. You can edit the colors and fonts throughout your email and then run specific tests to ensure your email quality across multiple platforms.

Your can be sure your code renders correctly if you use a drag-and-drop builder to build emails like this, with images, buttons, and text.


Stick with in-line CSS.

Most email clients support CSS. Just make sure you use in-line CSS coding to ensure that everything looks as intended across different devices.

Some email clients don’t support specific CSS stylesheets. If you want to edit the CSS of your emails, you’ll need to embed it directly within the HTML coding of your email. In-line CSS is attached to the HTML coding of your email. Otherwise, you’ll place your CSS coding within the head of your email.

Test your emails.

Running plenty of tests is the most important thing you can do, and Campaign Monitor makes it easy to test your emails as you design. You can also send test emails after you’ve finished your design.

Campaign Monitor allows you to test your emails across Gmail, Outlook, Apple iPhone, and over 30 other email clients throughout your design process. You don’t need to worry about your CSS. Instead, you can just focus on designing beautiful emails within a simple drag-and-drop builder.

Use responsive design.

A responsive design template will help you create a beautiful email, no matter which client or platform your subscribers use. Just focus on your content and let the template sort out the details. All you have to do is run a few tests to see how your design looks on different devices.

How to measure the results of your email campaigns

To figure out if your CSS is correct, you’ll want to run a few tests with your emails.

You can easily do this within the Campaign Monitor platform. As you’re creating your campaigns, you can easily run tests across different platforms to see how your email looks on Gmail, Outlook, Android, iPhone, and more.

You can also send out test emails to receive and view the email for yourself on your preferred platform. This is a surefire way to test: Open your email test on as many clients as you can.

Does it really matter?

Understanding how to code your emails is extremely important. Over half of your subscribers view your emails on mobile devices, so understanding how to optimize your emails for these platforms is crucial.

Emails need to look perfect across every email platform and device. Between using responsive templates or coding your emails with responsive design, and running plenty of tests, perfection can actually be attainable for your campaigns.

What now?

Now that you understand the importance of coding your emails properly, you can learn more about responsive design and properly coding your emails. Don’t necessarily get tied up in perfection—focus instead on designing emails that are easy to access, read, and click across each platform. Run plenty of tests and click through all the links, just to be sure.

Are you ready to learn more about responsive design? Check out the Campaign Monitor guide to responsive design.

This blog provides general information and discussion about email marketing and related subjects. The content provided in this blog ("Content”), should not be construed as and is not intended to constitute financial, legal or tax advice. You should seek the advice of professionals prior to acting upon any information contained in the Content. All Content is provided strictly “as is” and we make no warranty or representation of any kind regarding the Content.

Get started with Campaign Monitor today.

With our powerful yet easy-to-use tools, it's never been easier to make an impact with email marketing.

Try it for free