Guide to CSS support in email clients
Full report on all 24 clients
Download the complete guide
(PDF - 105 KB)
Download the complete guide
(Excel - 53 KB)
Designing an HTML email that renders consistently across the major email clients can be very time consuming. Support for even simple CSS varies considerably between clients, and even different versions of the same client.
We’ve put together this guide to save you the time and frustration of figuring it out for yourself. With 23 different email clients tested, we cover all the popular applications across desktop, web and mobile email.
As the number of email clients continues to grow, we’ve decided to simplify the web-based version of the guide to focus on the 10 most popular email clients on the market. For the complete report on all 24 email clients across the desktop, web and mobile email world, download the complete guide in PDF format.
| Style Element | Outlook 2000/03 |
Live Hotmail |
Yahoo! |
Yahoo! Classic |
Outlook 2007/10 |
Apple |
Apple iPhone |
Google Gmail |
Lotus Notes 6/7 |
Lotus Notes 8.5 |
AOL Desk 10 |
| <style> in <head> | |||||||||||
| <style> in <body> | |||||||||||
| Link Element | Outlook 2000/03 |
Live Hotmail |
Yahoo! |
Yahoo! Classic |
Outlook 2007/10 |
Apple |
Apple iPhone |
Google Gmail |
Lotus Notes 6/7 |
Lotus Notes 8.5 |
AOL Desk 10 |
| <link> in <head> | |||||||||||
| <link> in <body> | |||||||||||
| Selectors | Outlook 2000/03 |
Live Hotmail |
Yahoo! |
Yahoo! Classic |
Outlook 2007/10 |
Apple |
Apple iPhone |
Google Gmail |
Lotus Notes 6/7 |
Lotus Notes 8.5 |
AOL Desk 10 |
| e | |||||||||||
| * | |||||||||||
| e.className | |||||||||||
| e#id | |||||||||||
| e:link | |||||||||||
| e:active, e:hover | |||||||||||
| e:first-line | |||||||||||
| e:first-letter | |||||||||||
| e > f | |||||||||||
| e:focus | |||||||||||
| e+f | |||||||||||
| e[foo] | |||||||||||
| Text & Fonts | Outlook 2000/03 |
Live Hotmail |
Yahoo! |
Yahoo! Classic |
Outlook 2007/10 |
Apple |
Apple iPhone |
Google Gmail |
Lotus Notes 6/7 |
Lotus Notes 8.5 |
AOL Desk 10 |
| direction | |||||||||||
| font | |||||||||||
| font-family | |||||||||||
| font-style | |||||||||||
| font-variant | |||||||||||
| font-size | |||||||||||
| font-weight | |||||||||||
| letter-spacing | |||||||||||
| line-height | |||||||||||
| text-align | |||||||||||
| text-decoration | |||||||||||
| text-indent | |||||||||||
| text-overflow CSS3 | ![]() |
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| text-shadow CSS3 | ![]() |
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| text-transform | |||||||||||
| white-space | |||||||||||
| word-spacing | |||||||||||
| word-wrap CSS3 | ![]() |
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|||||||
| vertical-align | |||||||||||
| Color & Background | Outlook 2000/03 |
Live Hotmail |
Yahoo! |
Yahoo! Classic |
Outlook 2007/10 |
Apple |
Apple iPhone |
Google Gmail |
Lotus Notes 6/7 |
Lotus Notes 8.5 |
AOL Desk 10 |
| color | |||||||||||
| background | ![]() |
![]() |
|||||||||
| -moz-background CSS3 | |||||||||||
| -webkit-background CSS3 | |||||||||||
| background-color | |||||||||||
| background-image | |||||||||||
| background-position | |||||||||||
| background-repeat | |||||||||||
| -khtml-background-size CSS3 | |||||||||||
| -moz-background-size CSS3 | |||||||||||
| -o-background-size CSS3 | |||||||||||
| -webkit-background-size CSS3 | |||||||||||
| HSL Colors CSS3 | |||||||||||
| HSLA Colors CSS3 | |||||||||||
| Opacity CSS3 | |||||||||||
| RGBA Colors CSS3 | |||||||||||
| Box Model | Outlook 2000/03 |
Live Hotmail |
Yahoo! |
Yahoo! Classic |
Outlook 2007/10 |
Apple |
Apple iPhone |
Google Gmail |
Lotus Notes 6/7 |
Lotus Notes 8.5 |
AOL Desk 10 |
| border | |||||||||||
| -moz-border-color CSS3 | |||||||||||
| -moz-border-image CSS3 | |||||||||||
| -moz-border-radius CSS3 | |||||||||||
| -webkit-border-radius CSS3 | |||||||||||
| -moz-box-shadow CSS3 | |||||||||||
| -moz-box-sizing CSS3 | |||||||||||
| height | |||||||||||
| margin | |||||||||||
| padding | ![]() |
||||||||||
| width | |||||||||||
| Positioning & Display | Outlook 2000/03 |
Live Hotmail |
Yahoo! |
Yahoo! Classic |
Outlook 2007/10 |
Apple |
Apple iPhone |
Google Gmail |
Lotus Notes 6/7 |
Lotus Notes 8.5 |
AOL Desk 10 |
| bottom | |||||||||||
| clear | |||||||||||
| clip | |||||||||||
| cursor | |||||||||||
| display | |||||||||||
| float | |||||||||||
| left | |||||||||||
| opacity | |||||||||||
| outline CSS3 | ![]() |
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||||||||
| overflow | |||||||||||
| position | |||||||||||
| resize CSS3 | |||||||||||
| right | |||||||||||
| top | |||||||||||
| visibility | |||||||||||
| z-index | |||||||||||
| Lists | Outlook 2000/03 |
Live Hotmail |
Yahoo! |
Yahoo! Classic |
Outlook 2007/10 |
Apple |
Apple iPhone |
Google Gmail |
Lotus Notes 6/7 |
Lotus Notes 8.5 |
AOL Desk 10 |
| list-style-image | |||||||||||
| list-style-position | |||||||||||
| list-style-type | |||||||||||
| Tables | Outlook 2000/03 |
Live Hotmail |
Yahoo! |
Yahoo! Classic |
Outlook 2007/10 |
Apple |
Apple iPhone |
Google Gmail |
Lotus Notes 6/7 |
Lotus Notes 8.5 |
AOL Desk 10 |
| border-collapse | |||||||||||
| border-spacing | |||||||||||
| caption-side | |||||||||||
| empty-cells | |||||||||||
| table-layout | |||||||||||
| Total Market Share | 28% | 16% | 14% | 9% | 8% | 7% | 6% | 1% | 1% | ||
Version History
- 22 April 2010
-
Updated the guide with the results of our CSS3 email client tests. 21 new properties were added, with varying levels of support observed across the popular email clients. Notably, Webkit clients were big winners, including Apple Mail, iPhone Mail and soon, the iPad. At this stage, CSS3 is recommended for decorative purposes in email (such as adding text-shadow), due to poor support for layout and box-model properties.
- 27 August 2009
-
Added test results for the just launched MySpace Mail.
- 6 August 2009
-
A complete rewrite of the guide that included 7 new mobile email clients and a focus on the most popular email clients. The web-based version of the guide now features the 10 most popular email clients, while the PDF guide includes all 23 email clients tested.
- 26 August 2008
-
Replaced .Mac results with MobileMe.
- 11 June 2008
-
We increased the number of clients we tested, 21 in total now. Gmail and Outlook 2007 continue to be our primary focus since CSS support continues to be limited.
Positive signs from Microsoft though, Entourage 2008 was released with significantly better CSS support.
- 19 April 2007
-
Outlook 2007 was released with less CSS support than Outlook 2003. A major step back for HTML email design.
New Yahoo! mail was released with better support for CSS, a positive sign to say the least! Windows Live Mail replaced Hotmail and nixed some CSS support in the process.
- 30 March 2006
-
This was our original test. We added Windows Live Mail for the first time and ran through tests on Outlook 2003, AOL 9, Lotus Notes and Eudora.
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