Mirror your Mac screen to a Chromecast over local Wi-Fi — free, no subscription, no cables.
Sits in your menu bar. One click to start casting, one click to stop.
- macOS 14 Ventura or later (including macOS 15 Sequoia)
- Apple Silicon or Intel Mac
- ffmpeg installed via Homebrew:
brew install ffmpeg - Chromecast (any generation) on the same Wi-Fi network as your Mac
- Download the latest
Screencast-1.0.0.dmgfrom Releases - Open the DMG and drag Screencast to your Applications folder
- Launch it — a 📺 icon appears in your menu bar
- On first use, macOS will ask for Screen Recording permission — click Allow
- Turn on your TV / Chromecast
- Click the 📺 menu bar icon → Scan for Devices
- Click Start Casting
Your screen appears on the TV within a couple of seconds. The icon turns 🔴 while casting.
To stop: click the 🔴 icon → Stop Casting.
| Option | Choices | Default |
|---|---|---|
| FPS | 10 / 15 / 24 / 30 | 15 |
| Resolution | Native / 1080p / 720p / 576p | Native |
Lower FPS and resolution reduce CPU usage and improve stream stability on slower networks.
Settings are saved automatically and remembered between sessions.
- Screen capture — uses macOS CoreGraphics (
CGWindowListCreateImage) to grab raw frames at the chosen FPS - Encoding — pipes frames to ffmpeg, encoded with Apple's hardware H.264 encoder (
h264_videotoolbox) — low CPU, fast - Streaming — serves an HLS stream over HTTP on your local network
- Casting — tells the Chromecast to pull and play that stream via the Cast protocol
No cloud, no account, no data leaves your local network.
"Device: none found" Make sure your Chromecast and Mac are on the same Wi-Fi network. Try Scan for Devices again — discovery can take a few seconds.
TV shows only the desktop wallpaper / menu bar, not app windows Go to System Settings → Privacy & Security → Screen Recording, remove Screencast, add it back, then quit and relaunch the app.
Stream is choppy
Try lowering FPS to 10 or Resolution to 720p. Also check that ffmpeg is installed: which ffmpeg.
"ffmpeg not found" error
Install it: brew install ffmpeg
App blocked by Gatekeeper ("unidentified developer") Right-click the app → Open → Open. This is a one-time step for apps distributed outside the App Store.
git clone https://github.com/sashanicolas/screencast.git
cd screencast
python3 -m venv .venv && source .venv/bin/activate
pip install -r requirements.txt -r requirements-dev.txt
pip install py2app
bash scripts/build.sh
# .app lands in dist/- pychromecast — Cast protocol
- mss — screen capture via CoreGraphics
- rumps — macOS menu bar UI
- ffmpeg — H.264 encoding + HLS packaging
- py2app — .app bundle
MIT