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If memorizing our guide to CSS support is making you go cross-eyed, then meet Fractal, a web app for validating your CSS code across 24 of the most popular email clients. It’s also very easy to use and understand – simply pop in your HTML email code and get Fractal to work on generating a CSS compatibility report, flagging the CSS styles are either unsupported, or partially supported therein. What’s better, Fractal also backs up most flagged code with suggested fixes, plus you can also contribute your own.

Sheer simplicity aside, what we love about Fractal is how very useful it is for both beginner and old-hat HTML email coders alike. For folks making that uneasy transition from web to email, it’s a great way to get accustomed to what works in most email clients and what doesn’t. For the rest, it picks up subtle issues that are likely to crop up during consequent design and spam tests, such as borders not appearing in Lotus Notes and even the odd CSS typo.

A big thanks to Abs Farah for actively working on this important project – we’re certain you will find it to be just as useful for validating your HTML email code as we have.

  • Abs Farah

    Thank you for sharing fractal with everyone! It wouldn’t have been possible without the awesome guide you guys have compiled!

  • Morning Copy

    Cool tool. We’ll be adding Fractal testing to our workflow.

  • Justin

    This looks awesome! Perfect first step in the testing process before doing a full design and spam test through CM (save $5 up front for what could just be a stupid mistake). Thanks for the post!

  • Ric

    Keep up the good work.


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.
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