When sending emails from one email client to another, such as from Microsoft Outlook to Gmail, there are numerous variables that can affect how your email will appear to the recipient. One of the most significant factors is the font. If the recipient’s email client doesn’t support the font you’ve chosen, your email signature template might end up looking unprofessional, with text appearing jumbled, unreadable, or entirely different from what you intended.
This article delves into why using email-safe fonts is essential when sending emails across different email platforms and provides best practices for ensuring your emails appear polished and consistent across clients.
The following list of fonts are safe to use in email signatures, and are included in our Email Signature Rescue software, as most PCs and Macs have these fonts installed.
- Arial
- Tahoma
- Verdana
- Trebuchet
- Courier
- Lucida
- Times New Roman
- Georgia
- Palatino
- Impact (now included in Windows 10)
- Arial Black (now included in Windows 10)
What are email signature safe fonts?
We call the above fonts "email signature safe fonts" because they're safe to use as they are the default fonts that are pre-installed across different computers, devices and operating systems. They are on almost all devices.
What are web fonts?
Web fonts, like Google fonts on the other hand, are not found across multiple operating systems like Mac and PC's and devices like iOS and Android. They are designed and licensed for use on websites, to give Designers a broader range of fonts to get creative with.
Why cant I use web fonts in my email signatures?
You can technically use web fonts (such as Google Fonts or custom fonts) in email signatures, but there are several limitations and challenges that make it impractical and unreliable for many email clients. Here’s a breakdown of why using web fonts in email signatures is generally not recommended:
1. Limited Support Across Email Clients
The most significant issue with using web fonts in email signatures is lack of universal support across different email clients. Most major email clients, including Gmail, Yahoo Mail, Outlook, and many others, do not support web fonts. They rely on a predefined list of system fonts (email-safe fonts) that are universally installed across devices and platforms.
Email Clients that Don’t Support Web Fonts:
- Outlook (all versions): Outlook uses Microsoft Word’s rendering engine, which does not support web fonts.
- Gmail: While Gmail supports web fonts in the browser version, it does not support them in its mobile app.
- Yahoo Mail: Yahoo Mail doesn’t support web fonts either.
- Older email clients: Many older or less popular email clients (e.g., Lotus Notes) also do not support web fonts.
2. Font Fallback Issues
Even in email clients that do support web fonts, there's a potential risk of the font not loading properly. If a recipient’s email client cannot access the web font, it will fallback to a default system font, which may mess up the design of your email signature.
For example:
- If you specify "Roboto" as your web font and the email client doesn't support it, it will revert to a default system font like Arial or Times New Roman, which could alter the look of your email signature.
- The fallback fonts might be drastically different in terms of letter spacing, line height, and overall appearance, which could cause your signature to look disorganized or inconsistent.
3. Email Clients Block External Content
Many email clients, especially Gmail and Outlook, block external content (like images or fonts loaded from a web server) for security and privacy reasons. This means that:
- Web fonts hosted on external servers may not load at all, and the client might strip them out to prevent potential security risks.
- For the font to render correctly, the client needs to establish a connection to the server hosting the font file, but in some cases, this connection is blocked by default.
4. Rendering Inconsistencies
Even when email clients support web fonts, they may render them inconsistently across different devices, operating systems, or even app versions. This can lead to issues where a font looks fine in one client (like Apple Mail) but renders incorrectly in another (like Outlook).
5. Email Load Time and Size
Web fonts can increase the overall size of your email, especially if the font file is large or if you're using several different font weights and styles. Larger emails take longer to load, especially on mobile devices or slower internet connections.
Example:
- A standard web font may increase the size of your email by tens of kilobytes, and if you use multiple web fonts, the size can grow significantly. While this might not be an issue in some cases, for mobile users or those with limited data, this can negatively impact the user experience.
6. Device and Browser Variations
Even though modern email clients are better equipped to handle web fonts, they still differ in how they process and render them. For example:
- Desktop vs. Mobile: Some clients may render the font correctly on desktop but fail to do so on mobile, and vice versa.
- Web-based Clients vs. Desktop Clients: Gmail’s web interface may display the web font correctly, but the mobile app might not. Similarly, desktop versions of Outlook might not display web fonts, while its web version might support them.
7. Email Safe Fonts Are More Reliable
Because of all the above issues, the use of email-safe fonts (e.g., Arial, Times New Roman, Verdana, Helvetica) remains the most reliable method for ensuring consistent rendering. These fonts are pre-installed on virtually all devices, operating systems, and email clients, which means they’ll always display properly without requiring external resources.
8. Alternative Solutions for Branding and Design
If you're looking to add more visual appeal to your email signature without relying on web fonts, there are other alternatives:
- Images and Logos: Including your brand logo or other visual elements as images can help reinforce your brand identity. However, ensure that these images are optimized for email (small file size) and properly sized (with defined width and height).
- Email-safe Font Pairing: You can still make your email signature visually appealing by combining different email-safe fonts (e.g., pairing Arial for the body and Georgia for headings).
So while web fonts can look great in emails and are commonly used in websites, they come with a range of compatibility issues when used in email signatures. These issues include:
- Limited support across most email clients.
- The potential for font fallback, which can alter the appearance of your signature.
- Security and privacy concerns, as many email clients block external content like fonts.
- Rendering inconsistencies across devices and platforms.
- Increased email size and load time.
For these reasons, it’s best to stick with email-safe fonts that are universally supported, ensuring your email signature displays consistently across all devices and clients.
The Web Font Challenge: Gmail and Outlook Have Their Own Limitations
When it comes to creating HTML email signatures that look great across all email clients, it's not just Outlook causing headaches, Gmail's mobile app has its own quirks too. While Outlook remains the biggest hurdle for including web fonts in email signatures, with its limited support and complex rendering engine, Gmail's mobile app also doesn't support web fonts, meaning it defaults to system fonts like Arial and Times New Roman.
With Outlook's market share sitting at around 4%, and Apple Mail (~54%) and Gmail (~30%) taking the lion's share, the decision of whether to cater to Outlook’s limitations is yours. However, given the wide reach of Gmail (across both desktop and mobile) and the consistent behavior of email-safe fonts, it's often safer and more practical to stick with system fonts to ensure compatibility and avoid rendering issues.
Unless your recipient has that exact web font installed in their PC or Mac too (which most people won't), they won't see the email signature like you designed it and intended it to be seen. Instead they will see it with a fallback font like Arial or close New Roman and this can cause all sorts of other problems with line heights and throw out the entire email signature design.
Therefore if you want to be sure that the email signature you're sending is going to look the same when it's received by anyone, our best recommendation is stick to using the above email signature safe fonts that come pre-installed in macOS and Windows software.
Does Outlook support web fonts?
No, Outlook does not support web fonts in email signatures or emails. This applies to most versions of Outlook, both desktop and web-based, and is one of the biggest challenges for designers and marketers creating HTML emails.
Why Outlook Doesn't Support Web Fonts
- Rendering Engine: Outlook uses the Microsoft Word rendering engine to display emails. This engine doesn't support web fonts (such as Google Fonts or other externally linked font files). Instead, it relies on a set of system fonts installed on the user's device.
- Limited CSS Support: Outlook has limited support for modern CSS features, which includes the use of web fonts. While newer email clients and webmail platforms like Gmail and Apple Mail have started supporting web fonts, Outlook remains one of the most significant holdouts.
- External Content Restrictions: Outlook blocks or restricts external content (such as images or font files) for security reasons. This means it cannot fetch external resources like web fonts from a server, which makes it impossible to use them in emails.
Impact on Email Signature Design
Because Outlook doesn't support web fonts, you need to rely on email-safe fonts (such as Arial, Helvetica, Times New Roman, and Georgia) to ensure your email signatures are displayed correctly. If you try to use a web font, Outlook will fallback to the next available system font, which could cause layout issues or disrupt the intended design of your email signature.
Outlook does not support web fonts, which limits the use of custom fonts in emails for users on this platform. To ensure your email signature looks consistent across all email clients, it's best to rely on email-safe fonts and avoid using web fonts.
Does the Gmail mobile app (iOS & Android) support web fonts?
No, Gmail's mobile app (for both iOS and Android) does not support web fonts. While the web version of Gmail supports web fonts to some extent (in desktop browsers), this support does not extend to the mobile apps.
Why Doesn’t Gmail Mobile Support Web Fonts?
Here are the key reasons why Gmail’s mobile app doesn't support web fonts:
- Limited Rendering Engine Support:Gmail's mobile app uses a simplified rendering engine to optimize performance and minimize load times on mobile devices. Supporting web fonts requires more complex rendering processes, including downloading the font files from external sources. This can slow down performance, especially on mobile networks or older devices, which is why mobile Gmail opts to use system fonts instead.
- Mobile Email Optimization:Gmail for mobile is designed to prioritize speed and simplicity. By not loading external resources like web fonts, Gmail can keep email rendering more efficient. This also reduces the chances of security risks, such as downloading potentially harmful content from untrusted font servers.
- Security Concerns:Allowing external fonts means Gmail would need to download font files from a third-party server (e.g., Google Fonts or a custom font host). This increases the risk of security vulnerabilities such as phishing or malware through compromised font files. As a result, Gmail limits support for such features in the mobile app.
- Cross-Client Compatibility:If Gmail's mobile app were to support web fonts, it could lead to inconsistent rendering across devices and email clients. Different email clients handle web fonts differently, and Gmail's mobile app needs to ensure that email signatures and content are displayed reliably across all devices.
What Does This Mean for Your Email Signature?
If you use web fonts in your email signature template, Gmail mobile users will not see the font you intended. Instead, Gmail will fallback to a default system font (such as Arial, Times New Roman, or Helvetica). This can mess up the layout of your email signature, particularly if you've designed it with custom fonts in mind.
Gmail mobile apps do not support web fonts. For consistent display across both desktop and mobile devices, it's best to stick to email-safe fonts for email signatures and avoid using web fonts if you need to ensure a seamless, professional appearance across all platforms.
Fallback Fonts and Email Signatures
You could specify a fallback font that will show instead of the Google or Web font if someone doesn't have that particular Web or Google font installed on their PC or Mac. But again, our recommendation is to still just use the email signature safe fonts, as line heights and formatting of your email signature could be compromised if the height of the fallback font and the web font don't match up.
What about @font-face rules and email signatures?
New technologies are available to the web browser, for example the @font-face rule, which enables you to load any font you like into a web page, however @font-face is not supported in the vast majority of email software, like Gmail, Apple Mail and Outlook.The @font-face rule allows custom fonts to be loaded on a webpage. Once added to a stylesheet, the rule instructs the browser to download the font from where it is hosted, then display it as specified in the CSS.We have to code our email signature templates using older methods of coding, like tables and inline CSS, (similar to HTML emails) and the head of the HTML is someclose stripped on send from some email clients.
For these reasons, it's safer to only use the system fonts that come pre-loaded in both Mac and Windows software to ensure your email signature displays consistently across all major email client software, no matter which OS or email client it's received in.
Email-safe font email signature examples without fallback fonts
Not all is lost, check out these awesomely designed professional HTML email signature examples, made by Email Signature Rescue that include only email-safe fonts. Not bad hey! And you don't have to worry about them changing appearance on the receiver's end.
