Check the filename when an iPhone photo will not open or upload. A name ending in .heic often explains the error.
What HEIC is
HEIC (High Efficiency Image Container) is the format iPhones have used by default since 2017. Apple adopted it for a good reason: it stores photos at roughly half the size of an equivalent JPG, with better support for things like burst photos, live photos, and wide color. On an iPhone with tens of thousands of photos, that's a lot of storage saved.
HEIC uses HEVC compression, the same technology found in many 4K videos. Support outside the Apple ecosystem arrived late and remains uneven. Windows may need an extra codec, older Android devices can fail to open it, and many upload forms still reject it.
Convert a HEIC file to JPG
When a HEIC file won't open somewhere, the fastest solution is converting it to JPG; the format every device and website on earth accepts. You can do that right in your browser with the image format converter on this site: drop in the HEIC file, choose JPG (or PNG if it's a graphic), and download. The conversion happens locally on your device, which matters if the photo is a private document like an ID or a lease.
HEIC-to-JPG conversion re-encodes the image. Convert from the original HEIC and keep that original as the master copy.
Change the iPhone camera format
If you regularly share photos with non-Apple devices, change the camera setting:
- Open Settings → Camera → Formats.
- Switch from High Efficiency to Most Compatible.
Your iPhone will shoot JPG from then on. The files use roughly twice the storage and open more widely without conversion. You can also leave the camera on High Efficiency and enable Settings → Photos → Transfer to Mac or PC → Automatic for cable transfers.
Sharing from Apple apps
Some Apple apps convert HEIC to JPG during sharing. Email attachments, cloud-drive uploads, and direct file copies may preserve the HEIC format. This explains why the same photo works through Messages and fails on an upload form.
Should you convert your whole library?
Keep HEIC files in the original library and convert individual photos when a destination rejects them. Converting the whole library to JPG would use substantially more storage. See the image format guide for WebP, PNG, and AVIF.