CR3 File Format (.cr3)

A CR3 file holds raw sensor data in Canon Raw 3, a container built on the ISO base media file format that MP4 also uses, with the image itself coded by Canon's crx codec either losslessly or in the smaller C-RAW mode.

.cr3Image Files

CR3 at a glance#

Full name	Canon Digital Camera Raw Image Format
File extension	.cr3
Category	Image Files
Developer	Canon Inc.
First released	2018
MIME types	image/x-canon-cr3
Compression	Lossy or lossless, depending on how the file was written
FileFlip support	FileFlip reads this format but does not write it

What a .cr3 file can hold#

These are the things a CR3 file either supports or does not, and they are what decides whether a conversion keeps everything or quietly drops something.

Lossless compression	Yes
Embedded metadata	Yes
Colour profiles	Yes

Strengths and limitations of CR3#

What CR3 does well

The C-RAW mode writes a file roughly 40 percent smaller than the standard CR3 of the same shot, which matters most when filling cards during long shoots
The box structure it inherits from MP4 lets one file carry the raw image, embedded previews and the second Dual Pixel image as separate tracks
Every Canon EOS R body writes CR3, and so do recent DSLRs such as the EOS 90D, so one decoder covers Canon's current range

Where CR3 falls short

Software released before 2018 cannot read CR3 at all, because the move away from CR2's TIFF layout required a new decoder rather than an update
C-RAW compresses with wavelet quantization and is genuinely lossy, so the space it saves is not free the way a lossless option would be
Recording Dual Pixel RAW roughly doubles the file size, and only Canon's Digital Photo Professional can act on the extra data
Canon documents neither the container extensions nor the crx codec publicly, so third-party support was worked out by reverse engineering

CR3 is what a current Canon EOS camera writes in raw, and the real decision in the menu is whether to shoot standard CR3 or the smaller C-RAW.

Convert CR3 to JPEG when a photo needs to leave your editor for sharing or printing, or to DNG when an older piece of software refuses to recognize the format.

How to open a .cr3 file#

A .cr3 file opens in the programs below, grouped by the platform you are on. If you would rather not install anything, FileFlip converts CR3 into a format your machine already opens, and it does it in the browser tab rather than on a server.

Platform	Programs that open it
Windows	Canon Digital Photo Professional, Adobe Lightroom Classic, Adobe Photoshop, Capture One, Adobe Bridge
macOS	Canon Digital Photo Professional, Adobe Lightroom Classic, Adobe Photoshop, Capture One, Preview
Linux	darktable, RawTherapee, digiKam
iOS	Adobe Lightroom
Android	Adobe Lightroom
Web	FileFlip

CR3 questions people ask#

What is C-RAW and should I use it?

C-RAW is a compressed mode inside the CR3 format rather than a separate file type, and a C-RAW shot still comes off the card with a .CR3 extension. It cuts file size by roughly 40 percent using lossy wavelet compression, which is hard to see at normal viewing sizes but leaves slightly less room for heavy exposure recovery than standard CR3.

Why will my copy of Lightroom not open CR3 files?

CR3 arrived in 2018 with the EOS M50, and versions of Lightroom or Camera Raw older than that have no CR3 decoder, since Canon changed the container from CR2's TIFF layout to the ISO base media file format. Updating Lightroom or Camera Raw is the fix, and converting to DNG works for software that will never be updated.

Does converting CR3 to DNG lose anything?

Converting a CR3 file to DNG keeps the sensor data as it was captured, so image quality does not change. Canon-specific extras are what fall away, including the Dual Pixel autofocus data, which only Canon's Digital Photo Professional can use in the first place.

Why does Canon use CR3 instead of DNG?

Canon uses CR3 so it can put camera-specific data in the file, such as the Dual Pixel second image and its own lens correction information, without depending on a shared specification maintained by Adobe. Canon EOS cameras have no in-camera DNG option, so any DNG version of a CR3 is made afterwards on a computer.

Converting CR3 files#

FileFlip does not write .cr3 files, so nothing on the site converts into this format. It works as a source only.

Every conversion runs inside your browser. The file is read from your disk, the work happens on your own machine, and nothing is uploaded. How FileFlip works names the engine behind each family and how to verify that for yourself.