What Is a CR2 File? Canon's DSLR-Era RAW, Explained
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 |
How CR2 files work: what's actually inside
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.
The wrapper around all of this is TIFF, the same file family most RAW formats build on. In practice, one CR2 is several images stacked in a set order: a small thumbnail, a full-size JPEG preview the camera developed with your Picture Style, and behind them the sensor mosaic itself. Finder and card browsers stop at the previews; a RAW editor reads past them and develops the mosaic. Your Picture Style rides along the same way — as a note in the metadata, applied to the previews but never to the sensor data. Set the camera to Monochrome and the thumbnail arrives black and white while the mosaic underneath keeps every bit of color.
CR2 sizes and generations: 2004 to 2018
Canon introduced CR2 with the EOS-1D Mark II in early 2004 and kept writing it for fourteen years — long enough that files from opposite ends of the format's life share little beyond the extension. An early CR2 weighs less than a phone photo does now; a late one from a 5D Mark IV runs several times the size. Roughly by era:
| Era | Representative bodies | Sensors | Typical CR2 |
|---|---|---|---|
| 2004–2007 | 1D Mark II, 20D, original 5D, early Rebels | 8–13 MP | 7–13 MB |
| 2008–2012 | 5D Mark II, 7D, 60D, Rebel T2i/T3i | 15–21 MP | 20–25 MB |
| 2012–2018 | 5D Mark III and IV, 6D, 80D, 2000D | 18–30 MP | 25–40 MB |
Bit depth crept up alongside the megapixels: the earliest bodies recorded 12-bit CR2s, and with the 2007 generation — the 1D Mark III and 40D — 14-bit became the Canon norm, adding finer tonal steps exactly where shadow edits dig.
That same 2007 generation introduced sRAW, joined by mRAW in the 7D era: reduced-resolution options for shooters filling cards too fast. They're the one CR2 variant worth treating differently. The camera does part of the develop before writing them, so an sRAW carries fewer pixels and less editing latitude than a full CR2 — white balance and highlight recovery have less to grab. The files still open today; just don't expect them to bend as far as their full-size siblings.
The format's run ended where the mirrorless era began: the EOS M50 debuted CR3 in 2018, and the entry-level 2000D and 4000D, announced that same spring, became the last new cameras to write CR2.
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.
Can you still open CR2 files in 2026?
Yes — more easily than almost any other RAW you could have shot. Because the last CR2 cameras shipped in 2018, every serious editor finished adding support years ago: macOS, RevelRaw, Lightroom, Capture One and Canon's own Digital Photo Professional all read CR2, and the familiar "brand-new camera not supported yet" problem doesn't apply to a finished format. A CR2 from 2005 opens as readily on a new Mac as it did the week it was shot, which is exactly what you want from a negative.
Compare that with CRW, Canon's first RAW, where support has thinned enough that opening an archive takes planning. CR2 sits on the lucky side of that line: fourteen years of Canon DSLRs left behind too many archives for editors to drop, and support follows the install base. Move your files to a new machine and the only step is copying them over. The one caveat is sRAW and mRAW — a handful of apps handle those reduced-resolution variants less gracefully than standard CR2, so if part of your archive was shot that way, check it opens in your editor of choice before you commit to a workflow.
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. For the full picture of Canon RAW editing on a Mac, CR3 and CRW included, see our Canon hub.
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. Our guide to converting RAW to JPEG on a Mac walks through every route, Preview included.
Should you keep your CR2 archive?
Keep it. Those files are the negatives of the DSLR era — weddings, kids, travels, the whole back catalog — and each one still holds everything the sensor recorded, waiting for better software than existed when you shot it. RAW processing has improved faster than cameras have: a 2009 CR2 developed today, with AI scene detection and modern highlight recovery, comes out better than it ever could have back then.
Converting is for copies, not replacements. Export JPEGs when you want albums anyone can open, and treat each one as a print from the negative — a single interpretation, with the rest of the file's latitude left behind. DNG deserves the same framing: converting a CR2 to DNG repackages the sensor data into Adobe's container without making it any more editable, and with CR2 support this widespread there's nothing to rescue the files from. If you do convert for tidiness, keep the originals until you've confirmed every frame survived the trip.
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 CR2 files work?
A CR2 is a TIFF-based container holding several images at once: a small thumbnail, a full-size JPEG preview the camera developed with your Picture Style, and the raw sensor mosaic — one brightness reading per photosite, untouched. Thumbnails and browsers show the preview; a RAW editor develops the mosaic itself, which is why the two can look different.
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.
Can I still open CR2 files in 2026?
Yes. The last CR2 cameras shipped in 2018, so support finished maturing years ago: macOS, RevelRaw, Lightroom, Capture One and Canon's own Digital Photo Professional all read CR2. A file from 2005 opens as readily today as the day it was shot.
What are sRAW and mRAW?
Reduced-resolution RAW options on some CR2 bodies, starting with the 1D Mark III in 2007. The camera does part of the develop before writing them, so they carry fewer pixels and less editing latitude than a full CR2 — worth knowing before you push one hard in an editor.
Should I convert my CR2 archive to DNG or JPEG?
Keep the CR2s either way — every serious editor still reads them, so there's no urgency. Convert to JPEG for copies you want to share or view anywhere, and treat DNG as optional housekeeping rather than a rescue: it repackages the same data without making it more editable.
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.
Related reading: Canon RAW editing on a Mac · All RAW formats RevelRaw opens · CR3, Canon's current RAW · CRW, Canon's first RAW · What is an ARW file? · What is a NEF file?