Renders a Remotion composition to MP4 and runs the edit-and-re-render loop - CLI render commands, 1080p/4K/9:16 presets, concurrency tuning, codec selection, batch variants from a JSON data file, and Lambda for cloud rendering. Use when someone says "render this Remotion video", "export the composition to MP4", "the animation is too fast, fix and re-render", "batch render one video per customer", or "move rendering to Lambda". Do NOT use for authoring or restructuring scenes, animations, or components - use remotion-compose instead; do NOT use for project scaffolding and initial setup - use remotion-setup instead. This skill owns everything from a finished composition to a delivered file.
Click to play with sound.
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name: Remotion Render
description: Renders a Remotion composition to MP4 and runs the edit-and-re-render loop - CLI render commands, 1080p/4K/9:16 presets, concurrency tuning, codec selection, batch variants from a JSON data file, and Lambda for cloud rendering. Use when someone says "render this Remotion video", "export the composition to MP4", "the animation is too fast, fix and re-render", "batch render one video per customer", or "move rendering to Lambda". Do NOT use for authoring or restructuring scenes, animations, or components - use remotion-compose instead; do NOT use for project scaffolding and initial setup - use remotion-setup instead. This skill owns everything from a finished composition to a delivered file.
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# Remotion Render
Drive the render-and-iterate loop: turn a composition into an MP4, take natural-language feedback, make the smallest edit that satisfies it, and re-render. The costly failure mode is the opposite loop - rewriting whole scene files for a copy tweak, or re-rendering at full quality for every check - which destroys the approved work and the iteration speed that makes Remotion worth using.
## Operating procedure
### Step 1: Gather inputs
- Composition ID (the `id` on the `<Composition>` in `src/Root.tsx`, not a filename) and the entry point (the file calling `registerRoot`, typically `src/index.ts`).
- Target: platform/aspect (landscape 16:9, vertical 9:16, square), resolution (1080p default; 4K only on request), and whether transparency is needed.
- Machine cores (for concurrency) and whether this is one render, an iteration session, or a batch.
### Step 2: The base render
```bash
npx remotion render src/index.ts <CompositionId> out/video.mp4
```
Default output is H.264 MP4 at the composition's own width/height/fps; Remotion creates `out/` if needed.
### Step 3: Resolution, fps, and codec presets… install to load the full skill