Open Source TypeScript Image Processing Software

LocalResizer is a privacy-first image processing tool that runs entirely in your browser using Canvas API — your files never leave your device. It offers intelligent compression with multiple strategies: PNG can be converted to WebP (preserving dimensions) or scaled down, while JPEG and WebP support quality-based compression with real-time progress tracking. Key features include precise resizing by target file size (20KB to 10MB) or pixel dimensions, batch processing for up to 20 images simultaneously, and platform-specific presets for YouTube thumbnails, Instagram posts, Discord avatars, and more. The tool supports format conversion with automatic annotations for size and format changes. Built with Astro 5 and React 19, LocalResizer uses a pSEO architecture with parameterized routing to support unlimited page expansion. It's fully responsive, works offline after first load, and requires no registration. Perfect for developers, designers, and content creators who value privacy an