What Is a HEIC (HEIF) File? iPhone Settings, Opening HEIC on Windows and JPG Conversion Quality
Why iPhones save photos as HEIC, the Most Compatible and transfer settings, how to open HEIC on Windows and Android, and what changes when converting HEIC to JPG.
If you've ever tried to upload an iPhone photo to a Windows PC or a government website and seen an "unsupported format" message, the file was most likely a HEIC. This article explains what HEIC is, how to configure it on the iPhone, and how to open and convert HEIC photos you've already taken.
How HEIF and HEIC differ
HEIF (High Efficiency Image File Format) is an image container format created by MPEG and standardized as ISO/IEC 23008-12 (first published by ISO in 2017). A container is a box that holds image data and extra information. When that box holds an image compressed with the HEVC (H.265) video codec, it's a HEIC — the .heic file your iPhone saves. Put an image compressed with the AV1 codec in the same HEIF-family box and you get AVIF.
A HEIF container can hold several images in one file (burst shots, the key image of a Live Photo), depth data (Portrait mode), thumbnails, EXIF metadata, editing information and more. It can store 10-bit color, so it's also used for HDR photos.
Why does the iPhone save photos as HEIC?
Because it can store the same quality in a smaller file than JPG. Apple introduced HEIF/HEVC capture in iOS 11, and according to Apple's support documentation, iPhone 7 and later models can shoot in this format. The biggest advantage is saving device storage and iCloud space.
Three iPhone settings
| Setting | Options | Effect |
|---|---|---|
| Settings > Camera > Formats | High Efficiency / Most Compatible | "Most Compatible" captures photos as JPEG and video as H.264 |
| Settings > Apps > Photos > Transfer to Mac or PC | Automatic / Keep Originals | With "Automatic," photos may be converted to JPEG and H.264 when imported over USB |
| Sharing photos (AirDrop, Messages, Mail) | Decided automatically | If the receiving device doesn't support HEIF, photos may be converted to JPEG or similar |
- If you want future photos as JPG, set the camera format to "Most Compatible." The trade-off is larger files per photo.
- If you need JPG when moving existing photos to a PC, leave the transfer setting on "Automatic." According to Apple, turning on "Keep Originals" transfers HEIC files as-is without conversion.
- Menu names and locations may vary slightly by iOS version.
Opening HEIC on Windows
Windows often doesn't fully support HEIC out of the box. Installing HEIF Image Extensions from the Microsoft Store lets the Photos app and File Explorer handle HEIF files, and because the images inside HEIC are compressed with HEVC, you may also need HEVC Video Extensions depending on your setup. On locked-down machines such as work PCs where Store installs are blocked, you can't install the extensions, so converting the files to JPG is faster.
Android and HEIC
According to the supported formats table in the Android developer documentation, Android supports HEIF decoding (opening) from Android 8.0, but the platform doesn't provide a built-in encoder (saving). So HEIC photos received from an iPhone open in the gallery on most recent Android devices, but support may vary from app to app. Some Android manufacturers' camera apps offer a separate option to save in HEIF.
How to tell whether a file is really HEIC
Extensions are easy to change, so they can't be trusted. HEIF-family files have the marker ftyp near the start of the file (bytes 5–8), followed immediately by a brand name such as heic, heix or mif1. A JPG, by contrast, starts with the bytes FF D8, and a PNG with 89 50 4E 47. If a file has a .jpg extension but won't open, it may actually be HEIC. Conversion tools judge by the contents in cases like this, so just drop it in as-is.
HEIC support in web browsers
According to Can I use, the only browser that displays HEIC images directly on web pages is Safari 17 and later (macOS and iOS); Chrome, Edge and Firefox don't support it. That's about 15% of global browser usage share. That's why most website upload forms don't accept HEIC, or convert it on the server if they do. The complexity of HEVC patent licensing is often cited as the reason browser support hasn't grown.
Quality and file size when converting to JPG
- Quality: both HEIC and JPG are lossy, so converting adds one more round of loss. Saving at around quality 90 keeps it at a level that's hard to tell apart by eye.
- File size: JPG needs more bytes for the same quality. It's normal for the converted file to be larger than the original HEIC. If there's a size limit, as with application uploads, reduce the resolution during conversion.
- Color: iPhone photos are sometimes stored in a wider color gamut than sRGB, such as Display P3. If the conversion tool doesn't handle the color profile properly, colors can look slightly washed out.
- HDR and depth data: JPG is 8-bit and can't hold auxiliary images, so HDR brightness information and Portrait-mode depth data are dropped in conversion.
- Metadata: depending on the conversion method, EXIF such as the shooting location may be kept or removed. If you're worried about privacy, check whether location data remains after converting (EXIF metadata and privacy).
What happens to Live Photos?
An iPhone Live Photo pairs a single still image with a short video covering a few seconds before and after. Converting HEIC to JPG keeps only the still image; the motion isn't included. To share the moving version, save it as a video in the Photos app or use the sharing options. Also, burst photos often convert only the key photo, so pick and save the shots you need separately in the Photos app.
Convert right in your browser
The HEIC to JPG tool decodes and encodes inside this browser without sending your photos to a server. You can drop in several files at once and download them as a ZIP, and if you also need to reduce the file size, follow up with Compress Image. The specs of the HEIC format itself are in the HEIC format entry.
Frequently asked questions
Why does the file get bigger when I convert HEIC to JPG?
HEIC is compressed with the HEVC video codec, which is more efficient than JPG. Keeping the same quality in JPG takes more bytes, so it's normal for the converted file to be larger than the original HEIC.
Photos I send from my iPhone sometimes arrive as JPG. Why?
According to Apple, when you share via AirDrop, Messages or Mail and the receiving device doesn't support HEIF, the photo may be automatically converted to a more compatible format such as JPEG. When syncing with iCloud Photos, the original format is kept.
Can't I just rename a HEIC file's extension to .jpg?
The extension is only a name; the data inside is still HEIC. Upload forms and programs that inspect the file contents will reject it or fail to open it. You need to actually convert it.
Sources
- Apple Support — Using HEIF or HEVC media on Apple devices
- ISO/IEC 23008-12:2017 — Image File Format (HEIF)
- Nokia Technologies — HEIF technical information
- Microsoft Store — HEIF Image Extensions
- Microsoft Store — HEVC Video Extensions
- Can I use — HEIF/HEIC image format
- Android Developers — Supported media formats (images)