Modrinth is a free and open-source modding platform currently in beta. Among its features are a fast and easy-to-use search interface, along with ease of use and access for both mod developers and mod users.
According to the homepage, it intends to be the "world's most modder-friendly platform". It features an open source API coded in Rust, which can be used in various use cases, including both publishing and downloading mods.
Along with its backend API, it also has a comprehensive frontend, featuring a search function with various filters, including categories, mod loaders (currently Fabric and Forge), Minecraft version (including snapshots), and mod license.
The website's search feature also allows you to sort several different ways, including download count, follow count, update date, and creation date.
There are various additional features on the website, including follows, user profiles, and reports.
At this time, Modrinth only hosts mods, but there are future intentions to host things such as modpacks, datapacks, plugins, etc.