instructions

get-video-duration

Getting the duration of a video file in seconds with Mediabunny

vercel-labs/json-render/blob/HEAD/skills/remotion-best-practices/rules/get-video-duration.mdofficiallistedunreviewednot running here yet

Use skill

Set up

Skills are installed by placing their folder where your agent loads skills.

Part of the collection vercel-labs/json-render.

Copy the text of get-video-duration.md into the instructions file your agent reads (CLAUDE.md, AGENTS.md, .cursor/rules, …). Written for AI coding agents in general (from where the project keeps it; we have not run it).

README

synced Oct 14, 2026

Getting video duration with Mediabunny

Mediabunny can extract the duration of a video file. It works in browser, Node.js, and Bun environments.

Getting video duration

import { Input, ALL_FORMATS, UrlSource } from "mediabunny";

export const getVideoDuration = async (src: string) => {
  const input = new Input({
    formats: ALL_FORMATS,
    source: new UrlSource(src, {
      getRetryDelay: () => null,
    }),
  });

  const durationInSeconds = await input.computeDuration();
  return durationInSeconds;
};

Usage

const duration = await getVideoDuration("https://remotion.media/video.mp4");
console.log(duration); // e.g. 10.5 (seconds)

Using with local files

For local files, use FileSource instead of UrlSource:

import { Input, ALL_FORMATS, FileSource } from "mediabunny";

const input = new Input({
  formats: ALL_FORMATS,
  source: new FileSource(file), // File object from input or drag-drop
});

const durationInSeconds = await input.computeDuration();

Using with staticFile in Remotion

import { staticFile } from "remotion";

const duration = await getVideoDuration(staticFile("video.mp4"));