AI script to video: the chain cost from writer to export on our shelf

Every "AI script to video" tool page you'll land on tells you the same marketing beat: paste a script, press generate, get a video. The number you need is nowhere in that beat. What does the chain actually cost from first word to export? None of the big names price the whole thing because none of them charge for the writer, the storyboard, the engine and the caption on one meter.

Our shelf does. The script step bills on the same wallet as the engine step, and the chain cost is a number the picker prints before any of it runs. This is that number, on a real six-scene story, broken into the five steps and reconstructed as the finished-video cost in credits.

The chain, in five steps

1. Writer. We bill writer actions at a flat rate — 5 credits per generation, no matter what you ask the writer to do, with one exception. The convert action, which turns a long brief into a scene list the engine can read, is free. The daily brake is a limit of a hundred writer runs per account, enforced via an advisory lock at the request itself; the price has never been the throttle.
2. Storyboard. Not every scene gets a keyframe draft on our shelf, because the engines take references as images and the frames in a scene card double as references. In practice the storyboard step on our shelf is one free writer convert plus however many 4-second 480p drafts you choose to render on the cheapest engine as your scene card art.
3. Engine. This is almost all of the cost. We route a scene to Kling O3 Pro, Seedance 2.5, Veo 3.1 Fast, Seedance 2.0 Fast or Seedance 2.0 depending on the shot. The rate is per voiced or silent second at the chosen resolution and the picker prints it before the render.
4. Caption. Captioning bills 8 credits per started minute of audio actually transcribed, and it is free from the Creator plan up as a plan benefit rather than a discount.
5. Export. One flat 20 credits per export from the editor, whatever the timeline holds. The stitch runs on our own ffmpeg and there is no provider meter behind it, so the price is deliberately set at a point where nobody has to think about re-cutting a reel.

Five steps, two of which are often free. The real cost is step three and the useful math is comparing one of those scene choices against another.

A real chain cost: a six-scene story, 72 seconds finished

I'll walk through a plausible 72-second serialized story. One locked character, two speaking parts in one scene, voiced throughout, 720p, delivered to feed.

The scenes

scene	length	engine	reason
1 — establishing wide	6s	Veo 3.1 Fast (silent)	place-first opener, no dialogue
2 — opener close-up	8s	Veo 3.1 Fast (voiced)	one line, native audio, clean lip-sync
3 — character walks on	12s	Kling O3 Pro (voiced)	element-locked, continuous camera
4 — two-shot conversation	15s	Kling O3 Pro (voiced)	two named characters, no cuts
5 — single long reveal	15s	Seedance 2.5 (voiced)	one unbroken take beyond Kling's 15s cap
6 — reaction close-up	16s	Kling O3 Pro (two 8s voiced shots joined)	element lock through a cut

Total 72 seconds of finished video, four engines across six rows.

The chain cost

step	detail	credits
writer: brief → scene list (convert)	1 free run	0
writer: six scene-card titles and prompts	6 × 5 cr	30
storyboard: six 4-second 480p drafts (Seedance 2.0 Fast)	6 × 4s × 25 cr/s	600
engine, scene 1: Veo 6s silent 720p	6 × 20 cr/s	120
engine, scene 2: Veo 8s voiced 720p	8 × 30 cr/s	240
engine, scene 3: Kling 12s voiced 720p	12 × 30 cr/s	360
engine, scene 4: Kling 15s voiced 720p	15 × 30 cr/s	450
engine, scene 5: Seedance 2.5 15s voiced 720p	15 × 70 cr/s	1,050
engine, scene 6: Kling 16s voiced 720p (two 8s joined)	16 × 30 cr/s	480
caption: 72s = 2 started minutes	2 × 8 cr	16 (free on Creator up)
export: one timeline	flat	20
chain total (Lite / Starter)		3,366
chain total (Creator up, caption free)		3,350

At Lite's one-cent-a-credit rate, 3,366 credits is $33.66 for 72 seconds of finished voiced video. On Creator ($45/month for 6,000 credits, 0.75c a credit), it is $25.13. The Creator plan can land roughly 1.8 of these a month before the top-up stack is needed.

A competitor who charges $27/month for a plan that caps at 60 seconds of generative content is pricing against the engine step alone, with the writer, the storyboard, the caption and the export bundled into "a plan". Ours bundles none of them; every step is a credit line and the chain total is the sum. On a two-episode month that is the honest number.

What the drafts cost, and why they matter

The 600-credit storyboard line above is six 4-second 480p drafts on Seedance 2.0 Fast at 25 cr/s. That is a decision we make deliberately: a draft on 2.0 Fast is $0.0025 of our smallest cost tier, which is cheap enough that nobody skips the draft to save money. On Kling the equivalent draft is 480 credits for six 4-second voiced shots; on Seedance 2.5 at 720p it is 1,680. The 480p 2.0 Fast draft gives you the composition, the camera, the moment — enough to approve or kill the scene before you spend on the final render.

Where the draft would land on something not served by 2.0 Fast — a 1080p need, a scene with more than nine characters, a shot longer than fifteen seconds — the draft routes to the engine that actually quotes it, which is almost always 2.0 at 720p or 2.5 at 480p. The storyboard line in the chain cost moves accordingly.

Where the chain cost changes

Silent b-roll. Any scene silent on Kling drops from 30 to 24 credits a second — a 20% cut. The 15-second Kling two-shot in scene four voiced at 450 is 360 silent. On Veo the gap is 30 to 20 — a third off.

8-second ceilings. Veo's render enum is 4, 6, 8 — not a range. If the opener wants to be seven seconds, the engine quotes zero. Round to 6 or 8 and quote again; the picker refuses to quote a render the provider will refuse.

Resolution. Only Veo and the Seedance family quote 1080p today, and the price gap is sharp — 70 cr/s to 130 cr/s on 2.5. For a feed-only delivery, 720p is almost always the row.

Writer-heavy workflow. If the story takes twelve writer actions instead of six — more drafts, more tightens, more title variations — that is 60 extra credits, not 600. The writer is the cheapest step by two orders of magnitude on purpose, so the chain cost does not punish iteration on the brief.

The two things we actually optimise for

Press convert before writing a prompt. The convert action is free, and its job is to turn whatever shape of brief you have — a paragraph, a thread, a transcript — into a scene list the engine can take as reference. Running it before you touch a prompt is twelve minutes of writing you don't do. The scene list is also the thing you can hand back to the writer for tightening, which costs 5 credits per scene and buys you a per-scene rewrite without regenerating anything.

Keep the character block identical across every scene card. Reuse the exact descriptor — hair, eye colour, the one piece of clothing people will recognise, in the same order and the same wording — in every scene card. Change only the action, the camera and the location. The storyboard step on our shelf is where you lock the identity down; by the time scene 6 renders, every reference image is a frame the character has already appeared in.

Our own 9.7 million views across 30 days on @cevrico came from leaning on exactly this chain — convert, draft, render, caption, export — on a serialized story that priced out close to the 3,366 credits above per episode. Own results, your numbers will depend on what you ship and how far you iterate. A free account comes with 300 credits, enough for one writer convert, one scene list, and three 4-second 480p scene drafts on 2.0 Fast — the smallest honest version of a scene-list workflow. Open the writer and build one.