Link4 Ad Style and Implementation Guide

This is the style guide for ads appearing on the websites.

Actual Image Dimensions

To take advantage of double-resolution Retina (and similar) displays, the actual image dimensions should be double the displayed size, or 700px wide by 910px tall. Note that the ad will most likely never be displayed larger than 350px wide though.

The corners will be rounded (using CSS) with a 10-pixel radius curve, so avoid placing text in the corners of the ad.

Ad Display Sizes

The nominal displayed size for ads is 350px wide by 455px tall:

Sample ad 350 x 455

However, the ads will be used on mobile-friendly responsive websites where the ads may be shrunk on different devices, so the ads must be readable even when downsized to 229px wide as shown here:

Sample ad 350 x 455

Be sure that all of your text is still readable at 229px wide!

File Format and Size

The image format should be .jpg or .png, whichever results in smaller file size. File size should be less than 1MB.


You are free to use whatever colors you desire in your ad. However, we recommend a text-to-background contrast ratio of at least 4.5:1 (corresponding to WCAG 2.0 accessibility guidelines).


Link4 does not provide client-accessible analytics data for ads. Therefore, it is highly recommended that you create a unique landing page that the ad can point to or add a query string to your URL with the appropriate tracking functionality on your site.

If no query string is given, all ads will have the query string “ref=l4” added (starting 11/5/2021).