How to Convert HEIC to JPG on Mac, Windows, and Linux
Your iPhone takes photos in HEIC format. Most websites, apps, and services expect JPG. Here's how to convert them in seconds, without uploading to any cloud service.
Why are my photos HEIC?
Since iOS 11, iPhones save photos in HEIC (High Efficiency Image Container) by default. HEIC files are roughly half the size of equivalent JPGs at the same visual quality. Great for saving storage on your phone, but a headache when you need to share them.
Many websites, email clients, and apps still don't accept HEIC. When you hit "file not supported," you need a converter.
The problem with online converters
Searching "HEIC to JPG" returns dozens of websites that want you to upload your personal photos to their servers. That means your private photos travel across the internet, sit on someone else's machine while they're processed, and you have no guarantee they're deleted after.
For a photo of your lunch, that's probably fine. For photos of your family, your documents, or anything personal, it shouldn't be necessary.
Converting locally with ConvX
ConvX converts HEIC to JPG entirely on your machine. No uploads, no waiting for server processing, no privacy concerns.
Single file
convx convert photo.heic --to jpgWith a preset (recommended)
convx convert photo.heic --preset heic-to-jpgThe heic-to-jpg preset applies quality 90, high enough that you won't notice any difference from the original.
Batch convert an entire folder
convx convert "./photos/*.heic" --preset heic-to-jpg -j 4 -d ./convertedThis converts every HEIC file in the photos folder, using 4 parallel jobs, and saves the results to a converted directory.
Auto-convert as files arrive
convx watch ~/Downloads --preset heic-to-jpg --filter "*.heic,*.heif"Drop HEIC files into your Downloads folder and they'll automatically convert to JPG. Useful if you regularly AirDrop photos from your iPhone.
Using the desktop app
If you prefer a GUI, the ConvX desktop app lets you drag and drop HEIC files, adjust the quality slider, and convert with one click. The app shows a size comparison so you can see exactly how much space you're saving.
Quality comparison
At quality 90 (the heic-to-jpg preset default), a typical 12MP iPhone photo converts from ~2.5MB HEIC to ~3.8MB JPG. The visual quality is indistinguishable. At quality 80, the same photo drops to ~2.1MB with minimal perceptible difference.
Why not just change your iPhone settings?
You can set your iPhone to shoot in JPG instead of HEIC (Settings → Camera → Formats → Most Compatible), but you'll use roughly twice the storage. HEIC is genuinely a better format for storage. You just need a fast way to convert when sharing.