Developer builds browser-based HEIC converter that processes files locally via WebAssembly

A developer has built HEIC Tools, a client-side image converter that transforms Apple's HEIC format into JPG, PNG, or PDF entirely within the browser, without uploading files to any server. The tool was created out of frustration with existing online converters, which pose privacy risks, impose bandwidth costs, and enforce arbitrary usage limits. It uses WebAssembly through the open-source libheif-js module to decode Apple's proprietary format, while Web Workers keep the heavy processing off the main browser thread to prevent UI freezing. The converter also includes logic to identify and extract the highest-resolution frame from HEIC containers, which can hold multiple images such as thumbnails or Live Photo frames. Because all processing happens locally, the tool works even without an internet connection once the page is loaded.