Fractal Lab
Zoom into the Mandelbrot set in real time, watch the matching Julia set appear live as you move, and export a 4K wallpaper. Every pixel is computed on your GPU with emulated double precision for a deep, sharp zoom.
⚡ 100% in your browser — nothing is uploadedHow it works
The Mandelbrot set is the set of complex numbers c for which the simple rule z → z² + c, started at z = 0, never runs off to infinity. Color comes from how many steps a point takes to escape. That is a few thousand multiply-add operations for every single pixel, and Fractal Lab does all of them in parallel on your graphics card through a WebGL2 fragment shader. There is no server and no upload. The image you see was computed on your machine in the last few milliseconds.
How does it zoom so deep without going blocky?
GPUs natively do 32-bit single-precision floating point. That is fine for the first dozen zoom levels, but it falls apart once the screen spans a region smaller than about a millionth of the whole set, and you start to see chunky pixel blocks. Fractal Lab works around this by emulating double precision inside the shader using double-single arithmetic, where each coordinate is carried as a pair of floats that together hold roughly twice the bits. That is the trick that keeps the deep-zoom views sharp far past where a naive WebGL fractal breaks down.
The Mandelbrot and Julia connection
Every point inside the complex plane has its own Julia set, generated by the same z → z² + c rule but with c held fixed and z swept across the screen. Points near the boundary of the Mandelbrot set produce the most intricate, connected Julia sets. Move your cursor over the Mandelbrot view and the small preview shows that point's Julia set live, then click "Explore this Julia" to open it full screen and zoom in.
Make a wallpaper
Frame a view you like, pick a palette and color speed, and hit Export 4K wallpaper to download a 3840 by 2160 PNG rendered at full resolution. The share link button copies a URL that encodes the exact coordinates, zoom, palette, and mode, so you can bookmark a spot or send someone a deep-zoom location to land on instantly.
Is anything uploaded to a server?
No. The entire tool is one HTML file and all rendering happens on your device's GPU. Nothing leaves your browser and there is no sign-up.
Why does my fan spin up on deep zooms?
Deep zooms need more iterations per pixel and use the emulated double-precision path, which is heavier GPU work. Lower the iteration count or turn off auto iterations if you want it lighter.
It looks blocky at extreme zoom. Why?
Even emulated double precision eventually runs out of bits. To go arbitrarily deep you need arbitrary-precision arithmetic with perturbation theory, which is beyond what a single real-time shader does. Fractal Lab stays sharp far deeper than a standard WebGL fractal, but not infinitely.
Does it work on phones?
It runs on modern mobile browsers with WebGL2, though deep zooms are slower and the screen is small. A desktop with a discrete GPU gives the smoothest experience.
How do I save an image?
Use Export 4K wallpaper for a full-resolution PNG, or use the share link button to copy a URL that reopens the exact view.
I build tools like this every day.
Senior full-stack engineer, available for senior or contract work, fully remote. See the rest of the lab or get in touch.