Shdr Editor
Shdr is a live ESSL (GLSL) shader editor, viewer and validator powered by WebGL and built by Thibaut Despoulain (BKcore).
ShaderLab [ https://mgz.me ]
GLSL Editor
The Book of Shaders Editor
GLSL Sandbox Gallery
Shader Factory - Online GLSL Editor
Pixel Shaders Editor
Node Based Shader Editor in WebGL
Prototype Node Based Shader Editor in WebGL to edit and create materials interactively with nodes, where you can drag and drop textures and use multiple features similar to other editors
The Book of Shaders
Gentle step-by-step guide through the abstract and complex universe of Fragment Shaders.