So we need an easy of converting HEIC files on a Mac to the more common and universal JPEG/JPG format. Luckily, it’s easy to both open an HEIC file on a Mac, and convert it to JPEG.

High Efficiency Image Containers, or HEIC files, are typically unique to Apple products, so here’s how iPhone or iPad owners can convert their images to JPG to combat any compatibility issues ...

You can convert HEIC files to JPG on a Mac using the Preview app, then you can upload photos to websites that don't support the HEIC format.