Walmart Launches Rich Media APIs for Programmatic Product Video Management
What happened: On November 6, 2026, Walmart Marketplace published new Rich Media APIs that let sellers upload and manage product videos programmatically, instead of adding them one listing at a time through Seller Center. The launch is documented on Walmart's developer portal as available to US sellers.
What the API actually does
The core of the release is an Upload Media endpoint that creates a temporary, expiring location for a seller's system to push a video file directly to Walmart. The endpoint accepts MP4 or MOV files up to 500MB, requires a 16:9 aspect ratio between 1280x720 and 3840x2160, and caps clips at 5 to 45 seconds. H.264 or H.265 video with AAC, MP3, or PCM audio is required, and sellers can attach an optional closed-caption file in .srt or .vtt format. Each advertiser account can currently hold up to 200 media files, and the generated upload URL expires 15 minutes after it is issued and accepts only a single PUT request.
- Format: MP4 or MOV, H.264/H.265 video, AAC/MP3/PCM audio.
- Spec: 16:9 aspect ratio, 1280x720 to 3840x2160, 5-45 seconds, up to 500MB.
- Captions: optional .srt or .vtt file, recommended for WCAG accessibility.
- Limits: up to 200 media assets per account, 15-minute upload window per URL.
Why it matters for Amazon and Walmart brands
Up to now, adding video to a Walmart listing meant a manual upload through the UI for every SKU, which does not scale past a few dozen items. A programmatic upload endpoint means a catalog of a few hundred or a few thousand SKUs can get rich media attached through automation instead of a part-time job for someone on the catalog team. The same specs that make this useful also make it easy to get wrong: a video outside the 16:9 crop, the wrong codec, or a caption file in the wrong format fails silently or gets rejected at the 15-minute upload window, and a brand running this by hand across a large catalog will hit that friction constantly.
That is exactly the kind of recurring integration work that is worth automating rather than repeating manually. Brands with the engineering bandwidth are already looking at building a small internal service that pulls finished product video from their DAM, transcodes it to the required spec, and pushes it through the new endpoint on a schedule - the kind of project a custom software development team builds in weeks, not something to hand-roll inside a marketing team's spare time.
What to check before you build anything
- Confirm your video source files already meet or can be transcoded to the 16:9, H.264/H.265 spec before you design an upload pipeline around them.
- Count your current and near-term SKU video needs against the 200-asset-per-account cap so you know whether you need asset rotation logic.
- Decide where captions come from - .srt/.vtt generation is a separate step most DAM exports do not include by default.
- Treat the 15-minute upload window as a hard constraint in any automated job, with retry logic for expired URLs.
None of this is required to keep selling on Walmart today. It is an opportunity to close a gap between brands that still add video one listing at a time and those that treat their product catalog like a data pipeline.
