seal is a local tool for creating, storing and recording glsl fragment shaders directly in your browser.
No internet connection or installation required — just download the html file and it will open as a web page.

Built for artists and coders who need a lightweight playground to prototype and archive shaders. Ideal for those who prefer simplicity, privacy and control. Not for highly specific professional use but some edge-cases are covered.

All your data stays on your machine without accounts, servers or sync. Just remember to export frequently and before deleting browser data.

seal is stable and functional, aimed at staying minimal: just open the latest html released and start working.

• Live-coding: Write GLSL fragment shaders and see results in real time with error logs on top of the canvas.
• Rendering: Simple and minimal rendering loop powered by webgl. Support for most shadertoy custom variables.
• Recording: Play, pause, restart, record and download the shader to .webm with one click (square aspect ratio).
• Local Saving: Organize your shaders in folders and store them in your browser using indexedDB.
• Hiper-light: Compatible with virtually any modern browser including mobile, at just ~100KB.

WIP: webGL2 support > indexedDB to JSON export > Canvas overlapping & blending modes > Custom aspect ratios

Remember that your data stays in the browser until you export it! - back it up regularly if needed.

Pro tip: save as bookmark for easy access!