Model Details
Kling 2.1 Master is the premium master tier of the Kling text-to-video family, turning a written prompt into a short, cinematic clip with the highest motion quality and cinematic fidelity in the lineup. It is tuned for lifelike, physically coherent movement and rich detail, so the action, subject, and scene you describe render with strong prompt adherence and a polished, film-grade look. Choose a 5-second or 10-second clip and a 16:9, 9:16, or 1:1 aspect ratio to match landscape, vertical, or square delivery.
## Best for - Hero and establishing shots where motion quality and cinematic fidelity matter more than speed or cost - Turning a single descriptive prompt into a polished, film-grade clip with lifelike movement - Cinematic landscape (16:9) b-roll with camera motion and atmospheric detail - Social-ready vertical (9:16) clips and square (1:1) loops from text alone when top-tier quality is the priority
## Choose another model when - You want faster or cheaper generations and can trade some fidelity — use the Kling turbo text-to-video tier - You want to animate an existing photo or starting frame rather than generate from text alone — use an image-to-video model - You need a single still image, not motion — use a text-to-image model - You need clips longer than 10 seconds or fine frame-by-frame timeline control — use a dedicated long-form video tool
## Tips - Describe the subject, the action, and the setting in one coherent sentence; concrete motion verbs ("slowly pans", "rushes forward") translate well to on-screen movement - Use `negative_prompt` to suppress recurring artifacts such as blur, warping, or low-quality texture - Raise `cfg_scale` toward 1 for tighter prompt adherence, lower it toward 0 for looser, more creative motion (default 0.5 is a balanced starting point) - Match `aspect_ratio` to where the clip will run — 9:16 for stories/reels, 16:9 for landscape, 1:1 for feed loops
To run via the ModelRunner JavaScript client: ```js import { modelrunner } from "@modelrunner/client";
const result = await modelrunner.subscribe("kuaishou/kling-video/v2.1-master/text-to-video", { input: { prompt: "A serene mountain lake reflecting clouds at golden hour, gentle ripples on the water", duration: "5", aspect_ratio: "16:9", }, }); ```

