HEIC Format
HEIC (High Efficiency Image Container) stores one or more images using HEVC-based compression, commonly used by iPhones and iPads. Compared with JPG at similar visual quality, HEIC files are often smaller, which helps device storage. Compatibility outside Apple’s ecosystem is uneven: many Windows PCs, email clients, and online forms still expect JPG.
A HEIC file may contain image data, thumbnails, and metadata such as orientation and capture details. Sharing via some Apple settings converts to JPG automatically; cable or iCloud transfers frequently keep .heic extensions. When a form rejects an upload with a vague “invalid image” message, HEIC is a frequent cause.
FileShrinkr decodes HEIC in Server mode and re-encodes to JPG, WEBP, AVIF, PNG, or PDF. Browser mode may fall back to the server when the client cannot decode HEIC. For Base64 workflows, HEIC is converted on the server first, then encoding continues locally. Prefer JPG output for portals and email; use WEBP/AVIF when you control modern web delivery.