• Keep your videos short: Make them 15 seconds or less in length so that viewers are more inclined to watch all the way through. Instagram Stories and Facebook in-stream placements are also available for video ads that are 15 seconds or less. Trim existing footage that wasn't created with mobile in mind if you wish to use it.
• We recommend keeping your videos brief in general, however some positions do allow for lengthier videos. Videos can be up to 120 seconds long on Instagram feed and Audience Network, while videos can be up to 240 minutes long on Facebook feed, Marketplace, and Messenger Home.
• To get people's attention quickly, put the most interesting element of your video at the beginning. This should be done within the first three seconds.
• Choose a vertical or square aspect ratio to cover the most screen surface: Most people hold their phones vertically, so a vertical or square aspect ratio will cover the most screen area. 4:5 vertical video advertising are effective on Facebook, Instagram, and Audience Network. Use Instagram Stories, a free vertical video tool that's simple to use even if you're new to video.

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