Grok Imagine 30s vs Seedance 2.5 30s vs Veo extend

Three different 30-second stories: Grok Imagine Video is a 30s menu at 7cr / 720p with native audio; Seedance 2.5 is a 30s single pass at 47cr / 720p with native audio; Veo 3.1 extend is a 7s 720p continuation at 40cr, not a 30s generate.

"I need thirty seconds" is not a model pick. It is three objects that add up to the same clock. Pick the object first. Mixing them — asking Veo to be a 30-second generate, or asking Grok's menu to reason like a Seedance pass — is how a brief becomes four hops and a seam.

Grok Imagine Video is a 30-second menu

Grok Imagine Video publishes durations of 6s, 10s, 15s, 20s, and 30s. That is a menu. You choose a slot. You do not get 7s, 12s, or 28s. The catalog ceiling on the published brief is 720p. The sticker is 7 credits. audio is true — native audio is on this row.

Seven credits for a 30-second slot is the cheap long take in the catalog. It is not a 4K file, not Veo's 8-second cinematic generate, and not Seedance reasoning about a whole shot at once. Write the prompt as one continuous arc: establish, turn, close. Three ads glued with commas will pace like three ads glued with commas.

When 30s is not enough, Grok Imagine Extend continues an existing Grok Imagine clip. Durations on that row are 2s through 10s. Sticker: 8 credits. audio is false. The extension is picture continuation, not a second native-audio pass. Plan the bed on the 30-second generate; do not assume the hop sings.

Use Grok when the job is a budget 30-second hold, 720p is the delivery, and native audio on the menu slot is enough. Do not use it because xAI's composer on X felt like a studio. The catalog row is the job. The composer is a surface.

Seedance 2.5 is a 30-second single pass

Seedance 2.5 is the other 30-second object, and it is not a menu with a 30 at the end. The published brief is 4s through 30s in one-second steps, 720p, 47 credits, audio true. The product claim is a native 30-second single-shot from one text prompt: the model reasons about the whole take so motion, lighting, and subject identity hold from first frame to last.

That is why 47 is not 7 with a worse logo. You are paying for coherence across the duration, not for a longer dropdown. A 30-second Seedance pass that recasts the talent at 0:12 is still a miss — but it is a miss of a different architecture than a Grok slot that was always a picked length. Timestamp the beats in the prompt. One room. One action. Tempo shifts are allowed. Recasting is not.

4K is not this row. 720p at 47 credits is the 2.5 contract. Shorter lengths exist — 4s, 5s, 6s — and they are the honest first calls while you prove the shot holds. Do not buy 30s because the enum goes there.

Use Seedance 2.5 when the thirty seconds must be one thought: a demo that never cuts, a walk that cannot seam. Use Grok when the thirty seconds must be cheap and 720p with native audio is enough. Same clock. Different invoice.

Veo 3.1 extend is a 7-second continuation

VEO 3.1 Extend Video is not a 30-second generate. Read the row: category extend-video, duration 7s, resolution 720p, 40 credits, audio true. You feed it a clip. You get seven more seconds. That is a hop.

The generate it continues is Veo 3.1: 4s / 6s / 8s, official 4K tier, 40 credits, native audio. An 8-second 4K talking take is Veo's job. A 30-second Veo file is not a longer prompt. It is the 8-second base plus hops.

Arithmetic, in credits: one 8-second Veo 3.1 generate (40) plus three 7-second extends (40 each) lands around 29 seconds for 160 credits. Each hop only sees the tail of the last file, so drift compounds. The extend is 720p on the published brief even when the base was 4K — confirm the file you are stacking.

That pipeline is correct when the model has to stay Veo: always-on dialogue, a mouth you already approved on the 8-second pass. It is the wrong pipeline when you only needed thirty seconds of picture-plus-bed and could have opened Grok at 7 credits or Seedance at 47. Extending video length is the craft of hops. It is not a synonym for a 30-second generate. Keep Veo. Stop pretending a 7-second continuation is a 30-second model.

Three objects, three bills

Object	Row	Duration	Res	Credits	Audio	What "30s" means
Menu slot	Grok Imagine Video	6 / 10 / 15 / 20 / 30s	720p	7	true	You picked 30 from the list
Single pass	Seedance 2.5	4–30s	720p	47	true	One generate reasons the whole shot
Continuation	Veo 3.1 Extend	7s	720p	40	true	A hop. Not a 30s generate
Veo base	Veo 3.1	4 / 6 / 8s	4K	40	true	The clip you hop from

Route on the AI video generator by naming the object in the brief:

• "Thirty seconds, 720p, cheapest native-audio slot" → Grok Imagine Video, pick 30s, 7 credits.
• "Thirty seconds, one continuous action, identity has to hold" → Seedance 2.5, write the thirty seconds as one shot, 47 credits.
• "This 8-second Veo take must continue, same mouth, I will accept hops" → Veo 3.1 Extend, 7s, 40 credits per hop, 720p.

A 15-second plate stitched four times is a fourth object: an edit. It is not in this comparison. Do not smuggle it in by prompting "then they keep walking for thirty seconds" at an 8-second model.

The failure mode is the sentence "just make it longer." Grok can be longer because 30 is on the menu. Seedance can be longer because the pass goes to 30. Veo can continue because extend exists. None of those verbs is "make Veo a 30-second generate." Read the sticker. Pick the object.

FAQ

Is Grok Imagine Video a 30-second single pass like Seedance 2.5?

No. Grok publishes a duration menu that includes 30s, at 7 credits / 720p with native audio. Seedance 2.5 is a 4–30s single pass at 47 credits / 720p with native audio — one generate that is supposed to hold the shot. Same clock, different product.

Can Veo 3.1 generate 30 seconds if I ask nicely?

No. Veo 3.1 is 4 / 6 / 8 seconds. Extend adds 7s at 720p / 40 credits. Stack hops if the take must stay Veo. Do not prompt the 8-second row for a half-minute file.

Why is Seedance 47 credits when Grok is 7 for the same length?

Because they are not the same object. Seven credits buys a 30-second slot on Grok. Forty-seven buys a 30-second pass on Seedance 2.5. Cheap 720p with native audio: Grok. One continuous reasoned take: Seedance. Length is the shared number, not the shared SKU.

What if I need more than 30 seconds on Grok?

Grok Imagine Extend continues a Grok Imagine clip for 2–10s at 8 credits. audio is false on the extend row. Picture continues; do not claim a native-audio stem on the hop. Past that, you are in an editor, not in a longer generate.