Walmart rich media checklist (Sep 17, 2026): video rules, Sume steps
Walmart's video checklist, read from its own PDF updated Sep 17, 2026, in one table: 14 rules, which ones Sume can act on, and which stay your manual check.
Walmart Marketplace's video checklist has 14 rules across two pages, and Sume has a step for about half of them. Everything below comes from Walmart's Rich media: Technical requirements PDF, which says it was last updated on Sep 17, 2026 (read 2026-10-08). Sume does not check any of these rules for you, so treat the last column as the tool you would use, not a validation.
Technical rules (page 1)
Page 1 covers the file. Video files must be .mp4. The size limit is 100MB, which Walmart says is typically but not always accepted, and compressed videos sometimes still fail its API call. Closed captioning is optional but recommended for accessibility and WCAG.
Page 3 adds that submitted content is reviewed, that anything violating Walmart's Prohibited Products Policy is rejected, and that product claims must meet the FTC's Truth in Advertising rules. Those are policy checks, and no Sume endpoint touches them.
Accessibility rules (page 2)
Page 2 holds the rules that can fail a video even when the file is fine: no popups or redirect links, a music caption, a no-speech caption, plain language, no strobe, a flash limit, and text contrast. Most of them are about what you put in the render, so the Sume step is usually the prompt or the caption call.
| Walmart rule | Sume step |
|---|---|
| File must be .mp4 | Check the delivered file extension |
| 100MB size limit | Check file size; shorten with POST /v1/video-trim |
| Closed captions optional, filename ends .vtt | Transcript from POST /v1/video-inspect; you write the .vtt |
| No popups or redirect links in the video | Prompt discipline; no end card with a link |
| [MUSIC PLAYING] when only music, about 10 s | POST /v1/video-captions with cues |
| [NO SPEECH] when no sound, about 10 s | POST /v1/video-captions with cues |
| Plain language, eighth-grade level | Write script_text yourself and keep it short |
| Warn users of settings changes | Not applicable to a clip |
| Alt text on images, null alt on decorative | Not applicable to video |
| No embedded text except a logo, in images | Applies to images; keep clip text to captions |
| No strobe or flashing lights | Review stills from POST /v1/video-frames |
| Flashing at most 3 times in one second | 24-frame window with video-frames at[] |
| Contrast 4.5:1 normal, 3:1 over 18 px | design.colors on the caption call |
| Text over video must be legible | Check a captioned still |
Order of work
Generate, caption, then check. Burn the music or no-speech cue first, since it is part of the picture. Pull stills of the busiest second and the caption frames, review them, then confirm size and extension on the final file.
The caption cue and the transcript are the only steps that cost a fixed amount: $0.20 per caption job up to 60 seconds, and $0.01 per audio minute for the transcript plus compute.
- The PDF does not state a length, resolution or aspect ratio for videos, so Sume's own limits are the only constraint you have to plan around.
- Rich media is also restricted for some product types; see the post on gating alcohol, tobacco and firearms before generating.
- Walmart's own submission steps are in its Media Library, which Sume does not drive.
Sources
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