HEIC vs JPG: why iPhone photos need converting

Why Apple switched away from JPG

Apple made HEIC (High Efficiency Image Container) the default photo format on iPhone starting with iOS 11 in 2017. HEIC is built on the HEIF container format and encodes images with HEVC (H.265), the same video codec family used for efficient 4K video. Because HEVC's compression is significantly more advanced than JPG's decades-old approach, a HEIC photo typically stores at roughly half the file size of a JPG at comparable visual quality. For a phone that is constantly shooting photos and video and shipping them to iCloud over a metered connection, that difference adds up fast, which is exactly why Apple made the switch.

Where HEIC runs into trouble

The tradeoff is compatibility. JPG has been the universal photo format since the 1990s and is supported by essentially every device, website, and piece of software ever made. HEIC is much newer, and support outside Apple's own ecosystem is inconsistent: many Windows PCs need an additional codec installed before Photos or File Explorer can even show a thumbnail, and a large number of websites, upload forms, and older applications reject .heic files outright or handle them incorrectly. That gap is why HEIC to JPG is consistently one of the most searched image conversions on the web.

Does converting HEIC to JPG lose quality?

Converting HEIC to JPG means re-encoding the image, since JPG cannot store HEVC data directly. At a high JPG quality setting the difference is typically not visible to the eye, though because it is a lossy-to-lossy conversion there is technically a small amount of additional compression applied on top of what the camera already did. If you plan to edit a photo extensively, it is worth keeping the original HEIC (or converting to a lossless format like PNG or TIFF instead) and only producing a JPG for the final, shareable version.

When you actually need to convert

Convert HEIC to JPG when you need to upload a photo to a website or app that does not accept HEIC, send it to someone on Windows or Android who cannot open it easily, or use it in software that expects a standard photo format. Convert HEIC to PNG instead if you specifically need transparency or lossless editing, though note that HEIC photos from a camera do not have an alpha channel to begin with, so this mainly matters if you are working with edited or composited HEIC files. Convert HEIC to PDF when you need to share or print a photo as a document rather than an image file.

You do not have to change your phone's settings

iPhone does let you switch the camera to "Most Compatible" mode, which saves new photos as JPG instead of HEIC, but that gives up the storage savings for every future photo just to solve a problem that only shows up occasionally. Converting individual files as needed, only when you actually hit an incompatible upload form or app, keeps the storage benefit on your phone while still getting you a JPG whenever one is actually required.

Why does my iPhone save photos as HEIC instead of JPG?

HEIC uses the HEVC video codec, which compresses roughly twice as efficiently as JPG at similar visual quality, so Apple made it the default to save storage and reduce the size of photos backed up to iCloud.

Will converting HEIC to JPG reduce quality?

At a high JPG quality setting the difference is typically not visible. Some additional compression is technically applied because it is a lossy-to-lossy conversion, but for sharing and uploading purposes it is not something you will notice.

Can I open HEIC files on Windows without converting them?

Recent versions of Windows can often display HEIC thumbnails and previews once the appropriate codec extension is installed, but many older PCs, and most non-Apple software in general, still cannot open HEIC directly, which is when converting to JPG is the reliable option.