Colour tool is a work-in-progress website for dealing with colours in different colour spaces. I eventually plan to extend it to have more features, such as generating gradients. It's built using the chroma.js library, which made dealing with the different colour spaces really easy.
This ended up being a fun little project to work on, as it gave me a better understanding of how colours are represented in different formats, and what those differences actually mean. It also showed me how working with gradients in RGB space don't always work out, and helped me understand the limitations of RGB and HSL compared to colour spaces with wider gamuts.