I wanted a way to turn slides and PDFs into those hand-drawn whiteboard explainer videos without paying a monthly subscription for every few videos. So I built one. It's called Sketchcast, it's free, and it runs as a skill inside Claude.

This post walks you through setting it up and making your first video. It takes about five minutes to install, and a few minutes per video after that.

What you get

You give it a PDF, a PowerPoint deck, a Word file, some notes or a few photos. You get back an MP4 where each scene is drawn stroke by stroke, with a voiceover and captions timed to the voice.

A few things it does that I care about:

  • Five looks: whiteboard, chalk, blueprint, paper and kraft
  • Six natural-sounding voices (two American women, two American men, one British woman, one British man)
  • 720p up to 4K, in landscape or vertical 9:16 for Reels and WhatsApp Status
  • Captions in many languages, including Yoruba, Igbo, Hausa and French
  • No watermark, no credits, no sign-up

One honest limit up front: the voices only speak English for now. If you make a video in another language, you get full captions but no narration.

What you need

  • A Claude account. Any plan works.
  • Code execution turned on in Claude's Settings. The skill runs code to draw and render the video, so it won't work without this.
  • A laptop or desktop for the one-time install. Installing from the Claude mobile app gives people trouble, so use the web app in a browser or the desktop app. After that you can make videos from your phone too.

If you're on a Team or Enterprise plan, your workspace owner may need to allow skills first.

Step 1: Turn on code execution

Open Claude's Settings and switch on code execution. That's it for this step.

Step 2: Download the skill

Go to sketchcast.franwilltechnologies.com and pick a download:

  • Full version (11.3 MB). Has the voice files inside. Start with this one.
  • Lite version (193 KB). Use this if Claude refuses the bigger upload. It fetches the voice the first time you run it.

Don't unzip it. Claude wants the ZIP as it is.

Step 3: Upload it to Claude

Upload the ZIP as a skill in the Claude web or desktop app. You only do this once. There's a three-step install guide on the site with screenshots if you get stuck.

Make your first video

Start a new chat, attach your file and just ask. For example:

Turn this PDF into a whiteboard video.

Before it renders, Claude asks you two things:

  1. Size. 720p for phones and WhatsApp, 1080p for YouTube, 1440p for large monitors, or 4K for big screens. 4K takes several times longer, so I'd start with 720p or 1080p.
  2. Voice. Ask for short samples if you want to hear them first.

A few minutes later you get an MP4 in the chat. Most videos come out between one and three minutes long.

Prompts worth trying

Pick a look:

Make it in the chalkboard look.

Make it for phones:

Make it vertical for Reels.

Use a slide deck properly. Save your .pptx as a PDF first if you want to keep your own slide designs, then:

One scene per slide, and use my speaker notes for the narration.

Show the actual document. Page mode puts your real PDF pages on the board and reveals them line by line while the narrator explains:

Show my PDF pages while you explain them.

Use photos. Send JPG or PNG files (convert iPhone HEIC photos first), and they get pinned to the board when the narration reaches them, with drawn arrows or labels.

Change your mind afterwards:

Make scene 3 shorter.

Edits are quick because scenes you didn't touch get reused.

What about privacy?

This was important to me. I work in cybersecurity, and I didn't want a tool that quietly ships people's documents off somewhere. Your file stays in your own Claude session and nothing is sent to me. The only things the skill downloads are Python packages and the voice files, from fixed addresses. You can open the ZIP and read every line before you install it.

Limits to know about

  • Voices are English only for now. Other languages get captions without narration.
  • Up to 60 slides or pages per video.
  • Old .ppt and .doc files need saving in the newer format or as PDF first.
  • Videos count against your normal Claude usage, so very long or 4K videos use more of it.

What's next

I'm working on an Android app that won't need a Claude account at all. It will add more voices, your own logo on videos, and background music. You can sign up on the site to hear when it's out.

If you try it, I'd really like to know what you made with it and what broke. Drop a comment here.