What Is a CR2 File? Canon's DSLR-Era RAW, Explained

Q: What does CR2 stand for?

CR2 is the second generation of Canon RAW, introduced in 2004. It holds the unprocessed sensor data from the moment of exposure, plus metadata and embedded JPEG previews, in a TIFF-based structure like most RAW formats.

Q: Which cameras write CR2 files?

Canon DSLRs from 2004 until the transition to CR3 around 2018: the 5D series through the 5D Mark IV, 6D and 6D Mark II, the 7D series, the 80D, the Rebel line, early EOS M bodies, and PowerShot G-series compacts of that era. Newer bodies write CR3 instead.

Q: How do I open a CR2 file on a Mac?

macOS RAW support for CR2-era bodies is mature, so Preview opens the files with a double-click and Photos imports them. To actually develop the file rather than just view it, use a RAW editor — RevelRaw opens CR2 files with drag and drop on any Mac.

Q: What are sRAW and mRAW?

Reduced-resolution RAW variants some CR2-era bodies offered, trading pixels for smaller files. They develop like any other CR2, just at lower resolution — if you shot them years ago, they still open fine today.

Q: Can RevelRaw open CR2 files?

Yes. RevelRaw is built around Sony Alpha, but it opens Canon CR2 files all the same — drag one in or pick it from File > Open, and every preset, AI scene detection and fine-tune control works on it. Exports go out as JPEG, PNG, TIFF or HEIF.

Published July 24, 2026 · Daniel Tello · RevelRaw

A CR2 file is the second generation of Canon RAW, and for close to fifteen years it was simply what shooting RAW on a Canon meant. If you owned a 5D, a 7D, an 80D or any Rebel between 2004 and the late 2010s, your cards filled up with .CR2 files. Each one is a digital negative: the sensor's unprocessed readings from the instant of exposure, plus the camera's metadata and embedded JPEG previews — recorded before anyone decided what the photograph should look like.

Canon introduced CR2 in 2004 and kept writing it right up to the transition to CR3 around 2018. That makes CR2 the format of an enormous back catalog — weddings, travels and family archives from the whole DSLR era live in it. Here's what's inside a CR2 file, and how to work with one on a Mac today.

CR2 at a glance

Full name	Canon RAW, second generation
Extension	.CR2
Introduced	2004
Written by	Canon DSLRs from 2004 until the CR3 transition — 5D series through the 5D Mark IV, 6D and 6D Mark II, 7D series, 80D, the Rebel line, early EOS M bodies, PowerShot G-series compacts of that era
What it holds	Unprocessed sensor data at 12- or 14-bit precision depending on era, EXIF metadata, embedded JPEG previews
Structure	Built on TIFF, like most camera RAW formats
Typical size	Roughly 20–40 MB on 18–30 MP bodies; sRAW and mRAW variants smaller
Opens with	macOS Preview and Photos, Canon Digital Photo Professional, and RAW editors such as RevelRaw, Lightroom or Capture One

What's actually inside a CR2 file

A camera sensor doesn't record a picture. Each photosite records how much light hit it through a single-color filter — red, green or blue — arranged in a mosaic. A CR2 file stores those readings as they came off the sensor:

The mosaic sensor data. One brightness value per photosite, at 12- or 14-bit precision depending on the era of the body. No white balance, no sharpening, no Picture Style has been applied yet. Turning this mosaic into a viewable photograph is the job of your RAW editor.
Metadata. Camera body, lens, exposure settings, autofocus information, and the Picture Style you had dialed in. Editors read this to know how to interpret the data; nothing in it is baked into the pixels.
Embedded JPEG previews. The camera develops previews with its own processing and tucks them inside the CR2. That's what you saw on the camera's screen and what Finder shows as a thumbnail — which is why a RAW file can look one way as a thumbnail and another once an editor opens the real data.

CR2 vs CR3: which one your camera writes

The split falls at the mirrorless transition. Bodies from roughly 2018 onward — the EOS R line and its contemporaries — write CR3, a modern container with the compact C-RAW option. Everything before that writes CR2: a TIFF-based structure, one full-resolution flavor, occasionally joined by sRAW and mRAW, reduced-resolution variants some bodies offered to save card space. The extension in Finder tells you which side of the line your camera sits on.

CR2's age is quietly its advantage. Because the last CR2 cameras shipped years ago, RAW support for them is mature everywhere — the familiar "brand-new camera not supported yet" problem simply doesn't apply. A CR2 from 2005 opens as readily today as it did then, which is exactly what you want from a negative.

How to open CR2 files on a Mac

The basics are already on your Mac: macOS has long shipped RAW support for CR2-era bodies, so Preview opens the files with a double-click and Photos imports them without complaint. But Preview only shows you one develop of the RAW; it isn't an editor.

To actually develop the file — choose your own white balance, recover highlights, work the color — you need a RAW editor. RevelRaw is built around Sony Alpha, but it opens Canon CR2 files all the same: drag one in or pick it from File > Open, and AI scene detection ranks 40+ presets against your photo, with the standard fine-tune controls on top. Everything runs on your Mac; no file ever leaves it. Canon's own Digital Photo Professional and the big subscriptions — Lightroom, Capture One — read CR2 as well.

How to convert CR2 to JPEG

For a quick conversion with no editing, Preview can do it: open the CR2, then File > Export, choose JPEG, and set the quality. For a conversion that's actually developed — your exposure, your color — open the file in a RAW editor and export. RevelRaw exports JPEG, PNG, TIFF and HEIF, with platform presets for Instagram, print and web. Either way, keep the CR2 afterwards: it's the negative, and every JPEG is just one interpretation of it.

FAQ

What does CR2 stand for?

Canon RAW, second generation — successor to the original CRW and predecessor of CR3. It holds unprocessed sensor data, metadata and embedded previews in a TIFF-based structure, like most RAW formats.

Which cameras write CR2 files?

Canon DSLRs from 2004 until the CR3 transition around 2018: the 5D series through the 5D Mark IV, 6D and 6D Mark II, the 7D series, the 80D, the Rebel line, early EOS M bodies, and PowerShot G-series compacts of that era. Newer bodies write CR3.

How do I open a CR2 file on a Mac?

Double-click it: macOS RAW support for CR2-era bodies is mature, so Preview handles them and Photos imports them. To develop rather than just view the file, use a RAW editor such as RevelRaw.

What are sRAW and mRAW?

Reduced-resolution RAW variants some CR2 bodies offered — fewer pixels, smaller files. They develop like any other CR2; if you shot them years ago, they still open fine today.

Can RevelRaw open CR2 files?

Yes. Drag a CR2 in and it opens like any other RAW — presets, scene detection and fine-tune controls all work. Exports go out as JPEG, PNG, TIFF or HEIF.

See what's still in that CR2 archive. Download RevelRaw, drop one in, and watch it ranked against 40+ presets in seconds — with one full-quality export on the house. Get it on the Mac App Store.