CopyTrans HEIC for Windows - A plugin that lets you view HEIC photos on Windows and convert them to JPG by right-clicking.
Adobe Photoshop - Adobe Photoshop is a webtop application for editing images and photos online.
XnView MP - XnView is a free software that allows you to view, resize and edit your images. It supports more than 500 different formats!
GIMP - GIMP is a multiplatform photo manipulation tool.
iMazing HEIC Converter - iMazing HEIC converter is a free Mac and PC app which converts photos from HEIC to JPEG or PNG.
Affinity Photo - Affinity is the imaging and design suite for creative professionals exclusively for Mac.