Sharp

Sharp is the fastest image processing library in the Node.js ecosystem for resizing, converting formats, and optimizing uploads. It's a wrapper around libvips, the C library that runs circles around ImageMagick and GraphicsMagick.

Apache 2.0. Used by Next.js for its built-in image optimization, by Strapi, by Payload CMS, basically any serious Node.js project that touches images. Resize a 4000x3000 JPEG in 20ms instead of 200ms. That's the pitch.

Fully free. No paid tier. It's an npm package.

The catch: Sharp depends on native binaries (libvips), which means installation can fail on unusual platforms or restricted build environments. Serverless platforms like AWS Lambda need a compatible binary. It works but you might need a Lambda Layer. And Sharp is for server-side image processing only. If you need client-side image manipulation in the browser, look at the Canvas API or a library like Pica. For Python projects, Pillow is the equivalent.