If you need a tutorial or product demo without paying per video, explainroo is a free, open-source tool. It uses an AI coding agent - a program that writes and runs code from instructions - to create narrated videos from a script and scene descriptions.
explainroo suits narrated explainers and demos built from an app’s code or website. It does not record screen footage or provide a drag-and-drop editor.
When to choose explainroo or Camtasia
Choose explainroo if you want an agent to make a narrated explainer or product walkthrough and an MP4 meets your publishing needs. The kit is free under the MIT license, though the coding agent is a separate service with its own pricing. Optional AI illustrations also cost extra.
Camtasia records screen footage and edits video for tutorials, training videos, and software demos. Before relying on the offer, check its current free-start terms for export restrictions and watermarks, and confirm that your use is permitted. Choose based on whether you need captured footage and editing or a video generated from a script and scene descriptions.
What explainroo offers for free
explainroo creates the narration, scene visuals, timing, and music, then renders an MP4 on your computer. An AI coding agent writes two files: script.md, which contains the narration, and scenes.js, which describes what to draw and when. explainroo then turns those files into a video.
Kokoro, an open voice model, reads the script in American or British English without an account or API key. Narration is English-only. Whisper transcribes the recording and marks when each word is spoken, so scene changes align with the narration. Chrome draws the frames on an HTML canvas. Scenes can use hand-drawn-style lines, icons, charts, code, and screenshots. explainroo also creates background music and sound effects, then lowers the music while the voice speaks.
For a product demo, tell the agent which product to show and provide its code or website. The agent rebuilds the product’s screens using its colors, fonts, and button labels, then adds a pointer that clicks and types while the voice explains. This creates a walkthrough from reconstructed screens; it does not record the product in use.
You can choose among five visual styles in video.json: paper, clean, chalk, blueprint, and midnight. The same file controls pacing. explainroo supports wide video for YouTube and tall video for short-form platforms. It also supports portrait and square formats. Tall, portrait, and square videos include captions that highlight each spoken word.
The kit itself costs nothing per video. Optional AI illustrations are paid per image, and the coding agent has separate pricing. To run explainroo on your own computer, you need a recent version of Node.js. You also need FFmpeg and Chrome or Chromium. During setup, explainroo downloads the voice and timing models. You do not need a graphics card. The finished video is saved as videos/<name>/out/video.mp4.
How explainroo compares with Camtasia
Recording and editing
Camtasia records screen footage and edits video. explainroo generates narrated scenes and product walkthroughs. That difference matters for tutorials that need footage of a person using a live screen. explainroo does not edit existing camera footage, create talking avatars, or generate live-action AI footage, and it has no drag-and-drop editor. You describe the video to the agent and ask for revisions.
To try explainroo, paste this prompt into a coding agent that can run shell commands:
Make me a short explainer video about [your topic]. Use explainroo for it: clone the explainroo repository, read its AGENTS.md, and follow the steps.The agent sets up explainroo, writes the script and scenes, checks the result, and delivers an MP4. explainroo supports Claude Code, Codex, Pi, OpenCode, Gemini CLI, and other coding agents that run shell commands.
Free-plan limits
explainroo is a free, open-source kit with no per-video charge, separate from a hosted video editor’s free tier. The coding agent is a separate service, and optional AI illustrations are paid, so making a video can still involve costs.
Camtasia’s free-start terms should be checked against the video you plan to publish. Check the current export quality and whether Camtasia adds a watermark or limits recording. Also confirm that its terms allow your intended use. Those terms affect what it costs to finish and publish the video.
Exporting and sharing
explainroo renders an MP4 file on your computer. You can review that file and upload it to your chosen platform; explainroo does not promise a built-in publishing service. Before you start, confirm that your destination accepts MP4 files and supports the aspect ratio you need.
explainroo creates still images of the scenes and a contact sheet of frames. It also checks for cut-off or overlapping text and mispronounced words. Review the video yourself as well, especially the narration and any product details, before publishing. For Camtasia, check its current documentation for supported exports and sharing options that match your destination.
Choose the tool for your video
Use explainroo when you want a narrated explainer, a visual tutorial, or a product demo reconstructed from code or a website, and you are comfortable directing revisions through a coding agent. Start with a short topic or walkthrough, inspect the generated MP4, and adjust the script, scenes, or pace if needed.
Choose based on whether your video needs recorded footage and timeline editing. explainroo offers a free way to create narrated, scene-based videos, but it is not a like-for-like replacement for screen capture and timeline editing. If you need those capabilities, compare Camtasia’s current recording, editing, and export terms with your requirements before committing.
explainroo vs. Camtasia: Key Takeaways
- Match the production method to the video: explainroo generates narrated scenes and reconstructed product demos; Camtasia records and edits screen footage.
- Try explainroo with a focused prompt: Give a coding agent a topic or product, then review the MP4 it produces.
- Check the full cost: explainroo has no per-video charge, while the coding agent is separately priced and optional AI illustrations cost extra.
- Verify the final output: Review the narration, layout, and MP4 yourself before publishing, and check Camtasia’s current free-start terms if you are comparing costs.
Conclusion
explainroo is a free option for narrated explainers and product demos built from code or a website. Use it when you do not need live screen recording or timeline editing.
For a tutorial centered on recorded footage, compare Camtasia’s current terms and editing capabilities with your needs. For a scripted, scene-based video, explainroo generates an MP4 from instructions to a coding agent.
