TonniTools is built to run locally in your browser. Since no data ever leaves your device, everything works, even without internet.
Convert HEIC and HEIF photos — the default format on iPhones and newer Macs — into universally compatible JPG images. Upload one or many files at once, choose your JPG quality (max, high, medium, or low), and convert them all in a single batch. The tool decodes the HEIC format entirely in your browser using the heic-decode library, so your photos are never uploaded anywhere. See original and converted file sizes with percentage savings. Download files individually or all at once as a ZIP. Handles both single-image and multi-image HEIC containers, including files with RGB or RGBA pixel data.