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Coding for DPI Scaling in Outlook 2007-2013
Does Outlook sometimes make your email look like it was put through a garbage compactor and then fed through a taffy machine? Fonts are huge, tables look tiny and images are all out of whack? Worst of all, the email looks fine on your machine's Outlook! Why does it look different on your boss's laptop? The issue here is Outlook DPI scaling, a Windows setting that helps readers with visual impairments. DPI, or dots per inch, is a measure of how many dots (or pixels) can fit within a given space. The Outlook zoom problem is cropping up more and more as new high-DPI laptops often have the Outlook DPI scaling set as default. This problem affects Outlook 2007-2013. Luckily, Michael Muscat for found a solution and posted about it on Campaign Monitor's forum.
Table of content
-
01
How to Access DPI Settings in Windows -
02
Seeing the Zoomed-In Version of Your Email -
03
Why Does DPI Scaling Mangle My Email So Much? -
04
How Can I Code Email to Accommodate for Users with Desktop Scaling? - Use Inline Styles and px Units on Tables
- Use this Tag to Make VML Scale
- Use MSO Magic for cellspacing and cellpadding
- Outlook Getting You Down?
How to Access DPI Settings in Windows
You can access the Outlook DPI scaling on a Windows machine by navigating to your display settings. Click on "Make text and other items larger or smaller."
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Seeing the Zoomed-In Version of Your Email
Email on Acid's Campaign Precheck features a step where you can view your email zoomed in at 200%. This will give you a sense of what your font, images or design will look like if a user has high DPI settings. The zoom tool is part of Campaign Precheck's accessibility workflow, which helps you craft emails that are more accessible for users with disabilities or vision impairments. Here's an example of the zoom tool in action:
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Why Does DPI Scaling Mangle My Email So Much?
This display setting causes some parts of the email to scale in size, while others remain the same. That's why your email looks distorted and warped.- Widths and heights specified in HTML attributes remain pixel values.
- Widths and heights specified in VML code remain pixel values.
- Other pixel values (px) are converted to point (pt) values instead. This is why we see problems, like font display issues.
How Can I Code Email to Accommodate for Users with Desktop Scaling?
You can help control Outlook image scaling and increased font size in Outlook by making sure your email scales properly. By making a few simple code modifications, you can ensure the email will look great on any DPI setting.Use Inline Styles and px Units on Tables
You'll want to define the height using the attribute (for Gmail) then define the height and width inline using px. Tables that have a percentage-based width don't need any treatment, as they will scale without issue. Here's an example of a table formatted this way:<table>
<tr>
<td height="500" style="width: 500px;height: 500px;">
</td>
</tr>
</table>
Use this Tag to Make VML Scale
This solution is easy. You'll need to add the following to your head section to make VML scale properly.<html xmlns="http://www.w3.org/1999/xhtml"
xmlns:v="urn:schemas-microsoft-com:vml"
xmlns:o="urn:schemas-microsoft-com:office:office">
<head>
<!--[if gte mso 9]><xml>
<o:OfficeDocumentSettings>
<o:AllowPNG/>
<o:PixelsPerInch>96</o:PixelsPerInch>
</o:OfficeDocumentSettings>
</xml><![endif]-->
</head>
Use MSO Magic for cellspacing and cellpadding
Using these inline styles will allow you to create scalable cellspacing and cellpadding.<table cellspacing="10" cellpadding="10" style="mso-cellspacing: 10px; mso-padding-alt: 10px 10px 10px 10px">
...
</table>
That's it! You now have an email that is scalable in Outlook.
Outlook Getting You Down?
DPI scaling is hardly the only problem email developers face when coding for Outlook. If you're looking for more tips and tricks for coding emails for Outlook, check out these resources:- Our complete guide to Outlook
- How to Create Excellent Emails in Outlook.com
- How to Code Emails for Outlook 2016
- GIFs and Outlook: What Can We Do?
- How Do I Get Rid of the Lines in Outlook Emails?