Six seconds as a step and six as a full stop
Two pages publish six seconds and mean entirely different things by it. On one it is an increment that repeats up to two minutes inside a single request. On the other it is the whole of what the model produces, at forty-nine frames. As of 2026-09-22.
| What the pages state | Amazon Nova Reel | CogVideoX |
|---|---|---|
| What six seconds is | An increment | The complete length |
| Longest single request | Two minutes, in six second beats | Six seconds |
| A sixty second slot | One request | Ten requests, nine joins |
Inclusion rule. Length figures each page states, with the request count worked out by division. Nothing is said about how either set of pieces looks joined. Order. The meaning of the shared figure first.
1The same figure, a different kind of fact
An increment is a grain: legal lengths are six, twelve, eighteen and upward, so an eight second brief has no value to round to. A fixed length is a full stop: six seconds is what arrives, and a slot divides by it exactly.
Both make the arithmetic exact and only one makes it cheap. Ten pieces is nine seams that have to hold a face and a key light across separate inference runs; one request of ten beats has no seams an editor owns.
2Where each figure comes from
The increment is a product decision stated in a vendor user guide, with a model identifier condition attached to anything past the first beat. The fixed length is derived from a frame budget: forty-nine frames at eight a second, rounded to six.
That difference explains the rest of both rows. One publishes a single resolution and a twenty-four frame rate as a delivery format; the other publishes 720 by 480 with other sizes refused, and eight frames a second.
3Neither row leaves room to negotiate
No range, no menu and no tier to trade against length on either page. What a brief can change is the content and, on one of them, how many beats it asks for.
For advertising that is unusual. Most of this column offers a range or a ladder, and a plan written against these two rows has to start from the grain rather than from the beat, which is the reverse of how a shot list is normally built.
4The rest of the column behind these two
| Generator | Duration |
|---|---|
| Amazon Nova Reel | 6 s increments, up to two minutes |
| CogVideoX | 6 s, at 49 frames |
| Google Veo | 4, 6 or 8 s |
| Grok Imagine | 1 to 15 s |
| Hedra | 10 minutes |
| HeyGen | 30 minutes per scene |
| Kling AI | Not stated |
| LTX-Video | Frames, never seconds |
| MiniMax | 4 to 15 s |
| Pika | 5 s and 10 s, 20-25 s on Pikaframes |
| PixVerse | 1 to 15 s on version 6 |
| Runway | 5 to 15 s on Gen-4.5 |
| SceneMixer | Thirty seconds on the Wan tiers, fifteen on H3 |
| Vidu | Not stated |
| Wan 3.0 | 2 to 30 s |
Inclusion rule. Every generator this register carries, on the one column this pair disagrees about. Rows that state nothing keep their place and are marked hollow. Order. Alphabetical by generator name.
Why these two. The same number in the same column carries opposite consequences. One row fills a minute in a single job and the other needs ten, and a table showing only the figure would make them look identical.
- Video duration6 second increments, up to two minutesfrom the model table
- Video length6 seconds, at 49 framesfrom the model card table
5Sources
Read from the Amazon Nova user guide and the CogVideoX-5B model card, both checked 2026-09-22. The column is described on duration, and each entry has its own cell page at Amazon Nova Reel and CogVideoX, and the rule that keeps surfaces and generators apart is on method. Nearby pairs: HeyGen and Runway on size, TikTok and YouTube.