Use Native Video Captions For Maximum Recall of Ad Messaging

Native Ad Platform provides support for native video captions in the Native UI. You can use closed captioning to achieve maximum recall of your ad’s messaging.

Captions appear as an overlay to the video asset in the muted state and will disappear in the un-muted state. Advertisers can add a caption file to their videos via the Native UI, API and Bulk.

Key Benefits

  • Message recall is 60% higher for users exposed to closed captioning.

  • Captions provide valuable context for users who experience your ads without audio.

  • Closed captioning enhances the user experience and typically results in a 10% higher rate of enjoyment of your ad.

How It Works

Native simply sends the video + caption file in all ad responses. The supply endpoint will play the caption file if it can and, if not, it will play the video without captions (i.e., the status quo).

  1. Create a new ad, entitled Wonder Woman, from the Ads & keywords menu and choose the ad format as Video.

select ad format

The panel for the Video ad appears.

create a new ad
  1. In the Ad details panel, under Upload Video, drag and drop the video that you’ve created into the Video pane from your desktop, in this case, Wonder

upload the video
  1. While the video is loading, you can upload the Large rectangle image (which is required) into the image pane. The Square image will populate automatically. Ensure that these images are 1200x627 pixels and 627x627 pixels, respectively, according to image specification requirements.

  1. Select and open your caption file on your desktop, which includes your captions for the images and follows the defined specs for each image (shown below in the section on supported file types), drag and drop the caption file on the blank video screen.

drag drop file
  1. Click the view caption item at the bottom of the video.

  2. Enter the text for the Ad title and Ad description, along with your Company name and the Destination URL.

  3. In the Call-to-action button, enter in this case: Watch Now.

  4. Pause the video, save the ad and you’re good to go.

Supported File Types

Native closed captioning provides support for industry-standard file types, including:

  • .srt

  • .vtt


For its initial release, the .ttml file format is not supported.

A .srt caption file should contain the following elements:

  • A numeric counter identifying each sequential subtitle, in this format: (hours:minutes:seconds,milliseconds).

  • The time specified that the subtitle should appear on the screen, followed by this indicator: –> and the time it should disappear.

  • Subtitle text itself on one or more lines.

  • A blank line that contains no text, indicating the end of this subtitle.

For example:


00:00:05,000 –> 00:00:08,400

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00:00:09,600 –> 00:00:11,800

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