tinylog is a minimalistic logging platform JavaScript library I created which is primarily intended for online IDEs and implementing console.log() for browsers without native consoles. There is also a lite version intended for embedding in other JavaScript libraries. One such library that embeds tinylog lite is Processing.js, which uses it to implement Processing’s println().

There are also online demos of using tinylog that you can try out. The tinylog saved log viewer demo only works in browsers that support the W3C File API which is only Firefox as of now.