What is a HEIC file, and why is it awkward?
iPhones save photos as HEIC by default. The format is better than JPG on almost every axis, and that is exactly why it causes trouble: support outside Apple devices is uneven.
HEIC is the file extension for images stored in HEIF, a container built on the same foundations as modern video codecs. Apple made it the default for iPhone photos because it produces noticeably smaller files than JPG at comparable quality, and it supports features JPG never had: transparency, multiple images in one file, and higher bit depths.
Why it causes problems
A format is only useful if the software you depend on can read it. HEIC support requires a decoder built on the HEVC codec, which brings licensing considerations that many open-source projects have chosen to avoid. The result is uneven: Apple devices read it natively, recent Windows versions need a separately installed extension, many Android devices handle it, and a lot of desktop software and web platforms do not.
In practice the problem shows up as an upload rejected by a website, or a photo that will not open in an older editor. Converting to JPG or PNG solves it.
Which target format to choose
- JPG for photographs you are sharing or uploading. Smaller files, universally readable, no transparency.
- PNG if the image needs transparency or you want to avoid any further quality loss before editing it.
How this tool handles HEIC
Decoding HEIC needs libheif. Your browser can read HEIC on platforms that ship a decoder, in which case the conversion happens on your device and the file is never uploaded. Otherwise the file goes to the server, which can decode it when its PHP build has Imagick compiled with libheif.
Both cases are reported honestly per file. If neither path is available, the tool says so and explains what is missing rather than producing a file with a renamed extension. Renaming a HEIC to .jpg does not convert it, and every program you open it in will continue to see a HEIC file.
Convert an image now
The converter reads PNG, JPG, GIF, BMP, TIFF, ICO, WebP, AVIF, HEIC and SVG, and writes PNG, JPG, WebP, GIF, BMP, TIFF, ICO, AVIF and PDF. It states for each file whether the work happened on your device or on the server.
Converters mentioned in this guide
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