7 Top CSS Inline Editor Tools for Email To Try Out Today

On the surface, sending an HTML email should be a simple task – it's hardly new technology. Yet it can be incredibly complicated. Indeed, Smashing Magazine has claimed that "Email design and development is a beast. Email client vendors haven't been as progressive as web browser vendors in adopting new standards." This is definitely a task for your techies or development team, and not a quick job to give to the office junior on a Friday afternoon.

Some managers mistakenly believe that sending bulk emails is nothing but a scaled-up version of sending regular emails. Unfortunately, it's not as simple as that. You can't just type up an email and send it off to ten thousand people in your standard email host, like Gmail or Outlook. These services set a limit of 500 daily recipients, and they would look at you as a spammer if you tried to send more. For this reason, you need to use a specialist bulk email provider if you intend to engage in email marketing. 

You could send out simple text emails; many firms do, preferring its simplicity and knowing that it will be readable on virtually any device. However, in this visual era, text emails don't stand out. If you want your emails to match the rest of your branding, you really need to use HTML emails ... and that's when things get tricky. Building an HTML template can be hard work, even for a seasoned developer. 

However, there are now quite a few tools that can help you with your HTML email development, and some of these assist with CSS inline editing.

Top CSS Inline Editor Tools for Email:

Why Do You Need to Worry About CSS Inline Editing?

Like web pages, HTML emails involve a combination of HTML (HyperText Markup Language) and CSS (Cascading Style Sheets). The HTML gives your email's overall structure, while the CSS describes in detail how it looks. Effectively, the HTML tells your email client what goes where in your email, and the CSS goes into detail on how it should display.

When you design a webpage, you have three ways to include the CSS in your coding. Most web developers prefer to add their CSS in a separate style sheet. This means that you can easily change your site's style without altering the core HTML code. An alternative is to embed your styles in the <head> section of your main HTML document. This also keeps your CSS code relatively separate from your main HTML code and can be particularly useful for responsive designs, where you alter your coding to reflect the many ways we look at the web nowadays (on phones, tablets, laptops, even TVs.)

However, many email clients, including Gmail, ignore much CSS placed in the <head> of HTML documents. They also block access to external stylesheets. If you code your HTML email in the same way you do a standard webpage, you will be disappointed because the resulting email won't recognize your CSS styles and appear weirdly formatted. 

The third way to display CSS for a web page is to use inline styles. This means placing your CSS code amongst your HTML code, potentially messy and confusing for a sizable website (and very difficult to alter should you wish to change your site's look). With inline styles, you show items of CSS code that modify the look of raw HTML statements right beside each relevant HTML statement. 

The only consistent way to ensure that your emails display as you intend is to code them with the CSS inline, which can be time-consuming and messy if you haven't coded your site that way. Therefore, you need to use a tool to convert any code from a website you wish to use in your emails to include CSS inline.

Why Can HTML Emails be Complex to Handle?

Modern web developers may not be aware of the battles that occurred before the consistent standards we enjoy today. Before Google Chrome reigned in the world of internet browsers, there was a constant battle between Microsoft's Internet Explorer and Netscape Navigator. Since the introduction of HTML5 and CSS 3, relative harmony has existed in web programming, with clear standards across all competing browsers.

Unfortunately, the major email clients have not developed so cleanly. While most web browsers now consistently apply HTML and CSS standards, email clients like Gmail, Outlook, and the others do not. Indeed, in Outlook's case, Microsoft made a conscious decision that had the effect of making things worse. Before Outlook 2007, they used Internet Explorer to display HTML emails. But at that point, Microsoft decided to use Microsoft Word to render HTML emails (and indeed HTML code across all its Windows Desktop apps). Microsoft still displays HTML across its app this way, which lacks much of the compatibility a browser would.

This highlights the problem clearly. Sending an email in HTML is much more complicated than a mere text-based email. You have to ensure that it functions in at least four or five major web browsers and 12-15 different email clients (all of whom have their own way of rendering HTML emails).

And of course, most of these web browsers and email clients have been on the market for many iterations. Companies rarely start developing each version from scratch; they simply make modifications to the previous version. Therefore, this lack of consistent interpretation is getting worse over time, making developers' lives more difficult.

CSS Inline Editor Tools for Email

It is, of course, possible to hand-code inline CSS from the start, but this can quickly become unmanageable and unwieldy. Therefore, it makes sense to use a tool to do much of the hard work for you. With most of the tools you will find, you need to take any embedded code you have (or indeed any code you have in a separate stylesheet), copy it into your tool of choice, and the tool will create an inline version for you to use in your email client.

1. The Influencer Marketing Hub Website HTML to Email HTML Converter Tool

Our tool works differently from the rest of the products here. We've built a tool that can help your HTML email creation. Here we take the HTML from your webpage and make it suitable for your HTML emails.


  • Whether to inline styles in <style></style>

  • Whether to remove the original <style></style> tags after (possibly) inlining the css from them.

  • Preserves all media queries (and contained styles) within <style></style> tags as a refinement when removeStyleTags is true. Other styles are removed.

  • Preserves all @font-face within <style></style> tags as a refinement when removeStyleTags is true. Other styles are removed.

  • Whether to use any CSS pixel widths to create width attributes on elements set in juice.widthElements.

  • Whether to use any CSS pixel heights to create height attributes on elements set in juice.heightElements.

  • Whether to create attributes for styles in juice.styleToAttribute on elements set in juice.tableElements.

  • Whether to insert pseudo elements (::before and ::after) as <span> into the DOM. Note: Inserting pseudo elements will modify the DOM and may conflict with CSS selectors elsewhere on the page (e.g., :last-child).

  • Whether to output XML/XHTML with all tags closed. Note that the input must also be valid XML/XHTML or you will get undesirable results.

  • Preserves !important in values.



2. Mailchimp CSS Inliner Tool

Mailchimp recognizes that some email clients strip out <head> and <style> tags from emails, so it's best to have your CSS written inline within your markup. They know that writing inline CSS is time-consuming and repetitive, so they have built this conversion tool to automatically inline your email's CSS. All you have to do is to paste your email's HTML in the box on the page, click Convert, and you'll get a more email-friendly version that's ready to send. Mailchimp observes that if your email's CSS includes media queries for responsive styling, the inliner tool will leave those rule sets alone.

3. PutsMail CSS Inliner

PutsMail states that their CSS Inliner improves the compatibility and resilience of your design by inlining your styles. As with many of these tools, you simply copy your Body (HTML source code) and click on the button to generate inline CSS.

4. Campaign Monitor CSS Inliner

Campaign Monitor stresses that their CSS inliner handles media queries, web fonts, and other techniques that rely on some CSS being inlined. 

5. Premailer

Premailer has provided a version of a CSS inliner since 2007.  They have struggled to afford to keep it running in recent years, but Mr. Templates now makes Premailer's pre-flight for HTML email available. It asks for a URL as a source, or you can paste HTML as a source. It then asks for a query string to append to links. You can also select from various options before pushing Submit to prepare your code. 

6. HTML Email Responsive Email CSS Inliner

HTML Email's Responsive Email CSS Inliner works much like most of the products listed here. You enter your source HTML/CSS into a box, and then it displays the resulting Inlined CSS in another box. 

This tool has a more modern user interface than some of the other products, however, and it also shows your resulting email as it would look in somebody's email, both in desktop and mobile proportions.

HTML Email stresses the tool is powered by Juice. As it is an open-source project, it is continually being worked on and improved. 

HTML Email also gives some tips about how to use it with an external stylesheet. In this case, you will first have to copy your styles over between a <style> tag. They also observe that @media queries are ignored by default, so your responsive styles remain.

7. Litmus Builder

Another approach is to use a specialist email builder like Litmus Builder, to create your emails. Developers can use the HTML Code Editor to build emails and templates from scratch. Others ("email stakeholders," according to Litmus), can use the Visual Editor to create on-brand, error-free emails without needing to code.

You can even use ESP Syncing to automatically sync your code from Litmus Builder to your email service provider (ESP) with a click of a button. Once connected, whenever you make any changes to your code in Litmus Builder, it automatically updates in your ESP, too.

With Litmus Builder, you can automatically inline your email's CSS with a simple toggle. 

Frequently Asked Questions

What is a CSS Inliner tool?

Some email clients will strip outand

How do you make an inline CSS?

CSS can be added to HTML documents in two ways: through inline, by using the style attribute inside HTML elements, or internally, by using 

What app is used for CSS?

CSScomb is a coding style formatter which can help you sort CSS properties into a specific pre-configured order. CSS Compressor is another app you can use, which helps minimize and compress your CSS. Live CSS Editor is a Chrome and Safari extension that lets you freely write CSS rules on any site and see the results right away.

What is an example of inline CSS?

An example of inline CSS includes:

Inline CSS will then be applied on this heading:

How do I translate HTML to CSS?

You can translate HTML to CSS through the command line. Open a command-line prompt and run the code like this: 


Download, install and open VS Code.

Press CMD/CTRL+P to open the Quick Open dialog.

Type ext install tautvydasderzinskas. vscode-html-to-css.

Click the Install button, then the Enable button.

About the Author
With over 15 years in content marketing, Werner founded Influencer Marketing Hub in 2016. He successfully grew the platform to attract 5 million monthly visitors, making it a key site for brand marketers globally. His efforts led to the company's acquisition in 2020. Additionally, Werner's expertise has been recognized by major marketing and tech publications, including Forbes, TechCrunch, BBC and Wired.