Aether Renderer 0.3 🪼

Turn web animations into transparent video

HTML, CSS and JS in. WebM, MOV, GIF or MP4 out, with real alpha. Local, free and frame-perfect.

The Aether Renderer app switching between light and dark mode

How it works

1
Open your animation
An HTML file, a web address, a folder or ZIP of PNG frames. Or just drag it onto the window.
2
Pick size and format
WebM, MOV, GIF or MP4. Presets for Full HD, 4K, Reels/TikTok/Shorts, square and stickers.
3
Render
Every frame is stepped and captured in headless Chrome, then encoded. The same page gives the same video, every time.

Everything you need, nothing you don't

HTML to video

CSS animations, canvas, requestAnimationFrame, timers and the Web Animations API, all frozen to an exact clock per frame.

Frames to video

Exported a PNG sequence from Blender, After Effects or an AI tool? Drop the folder or ZIP in.

Real transparency

WebM (VP9 alpha) for the web, ProRes 4444 MOV for video editors, transparent GIF. Or fill the background with a color.

Frame-perfect

No screen recording, no dropped frames, no timing jitter. A slow machine makes the same video as a fast one.

Live preview and editor

See the page at the exact output size, edit the HTML in the Code tab, or start from a template.

Local and free

Runs on your computer. Nothing is uploaded, no account, no watermark. Open source, MIT licensed.

Made for

Titles and lower thirds. Design them in HTML, drop the transparent MOV on your timeline.
Stickers and emoji. Small transparent GIFs and WebMs for chats and sites.
Website loops. A hero animation as a light WebM instead of heavy JavaScript.
Social posts. Vertical 9:16 videos from a web page, frame by frame.

Download

Free and open source. Pick your system on the latest release:

macOS (.dmg)Windows (.msi)Linux (.AppImage)

You'll also need

FFmpeg on your PATH. On macOS: brew install ffmpeg

For HTML input, chrome-headless-shell (the app finds it automatically):

npx @puppeteer/browsers install chrome-headless-shell@stable --path ~/.cache/puppeteer

Prefer the command line?

The engine is two Rust crates you can use on their own:

cargo install aether-renderer-capture aether-renderer-core
aether-renderer-capture -i anim.html -o frames --fps 30 -d 4
aether-renderer-core -i frames -o anim.webm

aether-renderer-core · aether-renderer-capture