What Is a CR2 File? Canon's Raw Photo Format, and the Fourteen Years It Covers
A CR2 file is a raw photo from a Canon camera. Jump to your question below, or read it through in order.
A CR2 file is a raw photo from a Canon camera. Jump to your question below, or read it through in order.
A CR2 file is a raw photo from a Canon camera. CR2 stands for Canon Raw 2, and Canon cameras wrote it from 2004 until 2018.
Those dates matter more than anything else here. Older Canon bodies write CRW. Newer ones write CR3. Neither is a CR2. Plenty of guides get this wrong, including the older version of this page.
Shoot raw on a Canon and the camera skips the step where it decides how your photo should look. No sharpening, no contrast curve, no white balance baked in. What reaches the card is the reading from every photosite, with the settings recorded alongside as notes rather than decisions.
Photographers call that a digital negative, and the name fits. A negative is not the print. It holds more than the print does, and something has to develop it.
CR2 is one chapter of three. CRW came first, CR2 ran from 2004 to 2018 and CR3 has run since. All three are called Canon raw and no two are the same format inside.
.cr2Raw means unprocessed. One brightness number per photosite, laid out in the Bayer mosaic the sensor uses. The color you see later comes from demosaicing at development, not from the file. Beside it sit the shot settings, the lens, the timestamp and sometimes the location. Photographers call that metadata, and it travels with the picture.
Previews sit inside too, which is why file browsers show thumbnails of photos they cannot otherwise open. Section 4 pulls one apart properly.
Guides keep saying a CR2 holds what the camera's CCD captured. Canon's first home-grown DSLR was the EOS D30 of 2000, and it used a CMOS sensor. So did every Canon body that wrote CR2. CCD belongs to other makers of that era, not to Canon.
A second, unrelated thing uses .cr2. Poser, a 3D figure program, saves character rigging files with the same extension. Off your camera, it is a photo. Out of 3D modeling software, it is rigging for a figure.
Canon DSLRs from 2004 to 2018. The EOS 20D, 350D and 1D Mark II were first; the 5D Mark IV and 6D Mark II were near the end. Anything older writes CRW, anything newer writes CR3.
Canon has used three raw formats one after another. The boundary between them is a date rather than a kind of camera. Knowing which side of the line your body sits on answers most of the questions people bring here.
| Format | Years | Cameras |
|---|---|---|
.crw | 2000 to 2004 | EOS D30, D60, 10D, 300D, and the PowerShot G and S series |
.cr2 | 2004 to 2018 | From the EOS 20D, 350D and 1D Mark II through to the 5D Mark IV and 6D Mark II |
.cr3 | 2018 onward | From the EOS M50 on, including every EOS R body |
The 20D and 350D are the usual answer to which camera came first, and North America sold that 350D as the Digital Rebel XT. The EOS 1D Mark II arrived alongside them, and the compact PowerShot G9 joined later.
Bit depth moved during those years as well. Early bodies wrote 12-bit files. From 2007 on 14-bit became normal, and both kinds carry the same .cr2 extension.
Not sure which yours is? Look at the extension on the card. That is the entire test, and it is more reliable than any list, because Canon sometimes shipped bodies either side of a transition in the same year.
Watch for camera lists that put CRW bodies under CR2. It is a common mistake and it sends people hunting for the wrong software.
The tell is the EOS D30, D60, 10D or 300D. Those four are CRW cameras, every time. If a guide lists them as CR2 cameras, the rest of that guide is worth double-checking too.
CR2 and CR3 share a manufacturer and nothing else. CR2 is built on TIFF. CR3 is built on the same container family as MP4, with a different codec, so reading one tells software nothing about the other.
In 2018 Canon started the EOS R line and, with the M50, switched raw formats. The name barely changed and the file did, which is why software that has read Canon raw for twenty years can still refuse a photo from a new body.
Built on TIFF. Raw data compressed with lossless JPEG. Four directories inside, one of them the picture. Read by almost everything now.
Built like an MP4. Its successor uses Canon's own crx codec, with a lossy option. A different structure top to bottom, and it needs newer software.
The reverse-engineering reference for CR3 puts the break plainly: the TIFF-based format “is no more used by the M50 or EOSR”. Canon did not extend CR2. It started again.
| Question | CR2 | CR3 |
|---|---|---|
| Container | TIFF | ISO base media, or ISOBMFF, like MP4 |
| Compression | Lossless JPEG | Canon's crx codec |
| A smaller lossy option | No | Yes, called C-RAW and stored as craw |
| Old software reads it | Usually | Often not |
| Converts to DNG | Yes | Yes, with a recent converter |
Check the extension before you blame your software. Photos that will not open in software which happily handles your older ones are very often .cr3 sitting in folders of .cr2. They look identical in any list, and they are not the same thing.
A CR2 file is a TIFF file underneath, with four directories. Three hold previews of the photo. Only the fourth holds the raw sensor data, and that one is lossless JPEG compressed.
Canon invented no container. CR2 is built on TIFF, so the outer structure is ordinary and any TIFF reader can walk it. What makes it Canon sits eight bytes in.
Every CR2 opens 49 49 2A 00, which reads as II* and marks a little-endian TIFF. Nothing in those four bytes says Canon, and nothing says raw.
The Canon marker is at offset 8: letters CR, then major version 2, minor version 0, then a pointer to where your real photo lives. That header sits in space TIFF leaves free, so CR2 breaks no rules while carrying something extra.
| Directory | What it holds |
|---|---|
| IFD 0 | A quarter-size JPEG preview, plus the EXIF block and Canon's MakerNote |
| IFD 1 | A 160 by 120 thumbnail, also JPEG. Written 160x120 in the tags |
| IFD 2 | A small uncompressed preview, with no white balance applied |
| IFD 3 | The photograph. Full sensor data, lossless JPEG compressed |
Programmers name them IFD0, IFD1, IFD2 and IFD3, counting from zero. Three of the four are previews. That is why file browsers show pictures of photos they cannot develop, and why raw files opening small and flat got no further than IFD 0.
The raw image data in IFD 3 is compressed, in every CR2 ever written, using the old lossless JPEG standard. Nothing is thrown away, which is what lossless means, but the file is squeezed all the same. Lossless, not uncompressed.
Canon also cuts that data into vertical slices so a decoder can work on several at once. It is a detail you will never see, and it explains why raw files open faster than their size suggests.
The 5D Mark IV added a fifth directory. Its Dual Pixel RAW mode records a second view of the scene from the other half of every photosite, and Canon stored that as an extra IFD. Old software ignores it and shows the normal picture, which is exactly what you want from a format extension.
Free options cover almost everyone. Windows needs one download from the Microsoft Store. macOS needs nothing. To develop a photo rather than look at it, Canon's own Digital Photo Professional, darktable and RawTherapee all cost nothing.
Programs that open CR2 files come in two kinds, because two jobs here need different tools. Seeing your photo is one. Developing it, which means choosing the white balance and exposure your camera left open, is the other.
| Software | Cost | Why choose it |
|---|---|---|
| Digital Photo Professional | Free | Canon's own, DPP for short. Color matches the camera, because it uses the same profiles. Download it from Canon with your model |
| darktable | Free, open source | Runs on Windows, macOS and Linux. Closest free thing to Lightroom |
| RawTherapee | Free, open source | Strong Canon demosaicing and more control than most people need |
| Lightroom, Adobe Photoshop | Subscription | What most studios run, through Camera Raw |
| IrfanView, ACDSee | Free and paid | Fast viewers that batch-convert CR2 files to JPEG |
Under darktable, RawTherapee, GIMP and dozens of smaller tools sits the same engine, LibRaw. When free software gains support for a new Canon body, that is usually where it happened.
Picasa has been gone since 2016, and pages still recommend it. Google discontinued it, and the older version of this page named it twice, including in its specification table.
Anything telling you to open a CR2 in Picasa is pointing at software you cannot get. Those same lists usually name three or four other viewers that shut down years ago, UFRaw among them, which has had no release since 2015.
Taking the photo further afterwards? Photoshop PSD documents are where a developed CR2 usually ends up once you start working in layers.
Searching for a free CR2 viewer is riskier than it looks. The file itself is data and cannot run anything, but the download sites at the top of those searches bundle adware. Use the Microsoft Store, Canon's own support site, darktable.org or rawtherapee.com.
Two causes cover nearly everything. Your software is older than your camera, or the file is not a CR2 at all but a CR3 sitting beside them.
Raw support is added by camera model, so your editor does not read CR2 in general. It reads CR2 from its own list of Canon bodies, and a newer camera than your software falls off that list.
Canon owners have one trap other brands do not: two formats sit either side of 2018 and look alike in folder listings.
| What you see | What it usually means | Start with |
|---|---|---|
| Not supported, or an unknown format | Software older than the camera body | Update it, or check for .cr3 |
| Only some files in the folder open | A mix of CR2 and CR3 from two cameras | Sort by extension and look |
| Opens, but the edits do nothing | Preview only. You are looking at the embedded JPEG | A developer that reads IFD 3 |
| No thumbnails in File Explorer | Raw Image Extension is not installed | The Microsoft Store, free |
| Looks flat and gray beside the JPEG | Nothing is wrong. Raw arrives undeveloped | Any raw developer |
| Truly unreadable, in everything | A part copy or a bad card transfer | The memory card, before anything else |
Just bought a Canon body? Update your raw software before the first real shoot. Canon's own Digital Photo Professional supports a camera from the day it ships, because Canon makes both.
There is always a way through. Develop in Canon's software, export a TIFF then carry on in whatever you normally use until support arrives. It costs one extra step and nothing else.
Develop first, export second. JPEG suits sharing, TIFF suits further editing and DNG suits archiving. Keep the CR2 whatever you export, because the export cannot be undone.
Converting raw is not really conversion. It is development. You choose the white balance, exposure and contrast your camera left open, then write the result somewhere ordinary.
| Export to | Keeps | Best for |
|---|---|---|
| JPEG | 8 bits, lossy, small | Sending, posting, printing at a shop |
| TIFF | 16 bits, lossless, layers if you add them | More editing elsewhere |
| DNG | Everything. Still raw, still adjustable | Archiving. See what a DNG file is |
| PSD | Layers, masks, adjustment stacks | A Photoshop project |
Exports land as .jpg, .tif or .dng, under the same name in the same folder. Your CR2 stays where it was.
CR2 is closed, undocumented and tied to how long Canon keeps caring about cameras it stopped making in 2018. DNG is published, documented and readable by anything that reads raw at all. Adobe DNG Converter is free and converts CR2 files into DNG without developing them.
That matters more than it sounds. Free software tracks whatever volunteers can still test, and the bodies that wrote CR2 are already out of production. A DNG copy of your twenty-year-old photo is far likelier to open than the CR2 beside it.
JPEG exports are not backups of raw photos. Every one is a single interpretation, flattened to 8 bits, with your room to change your mind removed.
Delete the CR2 and keep the JPEG, and you have thrown away the negative and kept one print.
A JPEG is the camera's finished picture. A CR2 is the measurement behind it. Raw is a category; CR2 is Canon's entry in it, and Sony, Nikon and Fujifilm all have their own.
12 or 14 bits per pixel. White balance and exposure still open, wide room in shadows and highlights, 15MB to 35MB, needs a developer.
8 bits per pixel. Every decision already made and baked in. A few MB, opens anywhere and the only one you can send to somebody.
Neither wins outright. Shoot raw when the light is difficult or the photo matters. Shoot JPEG when you need to hand it over in the next ten minutes. Most Canon bodies write both at once, which settles the argument.
Camera raw files are a category rather than a format. Every maker of digital cameras built their own, none documented it and none work together.
| Extension | Made by | More |
|---|---|---|
.cr2 | Canon, 2004 to 2018 | This page |
.crw | Canon, before 2004 | See Canon CRW files |
.arw | Sony | See what an ARW file is |
.nef | Nikon | See the NEF file format |
.raf | Fujifilm | See Fujifilm RAF files |
.dng | Adobe, and open | See the DNG format |
You cannot turn a CR2 into an ARW or an NEF. They come from different companies and wrap different sensors. DNG is the only common ground, and it exists because Adobe built it.
Every one of these has the same weakness. Closed, undocumented and dependent on the manufacturer. That is why how a file format works matters when you are deciding what to keep photos in for twenty years.
CRW is the Canon raw format that came before CR2. It ran from 2000 to 2004 on the EOS D30, D60, 10D and 300D and on the PowerShot G and S series.
Canon's first raw format, the predecessor of everything here, shipped with the EOS D30 in 2000 and ran for four years. It is not TIFF and it is not CR2, though both come from Canon and both hold sensor data.
The EOS D30, D60, 10D and 300D, plus the PowerShot G1 through G6 and the PowerShot S30 through S70. Those are the bodies that pages routinely list under CR2 by mistake, including the older version of this one.
| Check | CRW | CR2 |
|---|---|---|
| Extension | .crw | .cr2 |
| Years | 2000 to 2004 | 2004 to 2018 |
| Built on | Canon's own layout | TIFF |
| Camera to look for | EOS D30, D60, 10D, 300D | EOS 20D, 350D, 1D Mark II onward |
Both formats still open. Canon's own software reads CRW, and so do darktable, RawTherapee and Adobe's DNG Converter. The problem is never that CRW stopped working; it is that people go looking for CR2 tools to open one.
Sitting on photos from an early Canon DSLR? Convert them to DNG for archiving while everything still reads them. Those cameras stopped selling twenty years ago and the software that supports them is all volunteer-maintained now.
Three Canon raw formats in twenty-five years is not unusual. Sony has four and Nikon keeps extending one. Every manufacturer eventually outgrows what they designed around the sensors of the day, and starts again.
Twelve or fourteen bits per photosite where a JPEG keeps eight, and nothing thrown away. Lossless compression only halves what is left. Reckon on 1.2MB for every megapixel your camera has.
Shoot raw and JPEG together, then look at both files. One weighs ten times what the other does. Nothing has gone wrong. Two files, two jobs. Only one of them is trying to stay small.
Multiply your megapixels by about 1.2 and you land close, because that is what 14 bits per photosite comes to once lossless JPEG has squeezed it.
| Sensor | Bodies | One CR2 |
|---|---|---|
| 8 megapixels | EOS 20D, 350D | 8MB to 10MB |
| 18 megapixels | EOS 7D, 600D | 20MB to 25MB |
| 22 megapixels | EOS 5D Mark III | 25MB to 28MB |
| 30 megapixels | EOS 5D Mark IV | 35MB to 40MB |
Two habits push those numbers up. Shooting raw and JPEG together writes both files, so budget for both. Dual Pixel RAW roughly doubles file size, because it records a second reading from every photosite.
Buying a memory card? 64GB holds around 1,700 photos from a 30 megapixel body, or half that shooting raw and JPEG together. Two smaller cards beat one big one, because a card failure then costs you half your day.
Sensor readings carry noise, and noise is close to random. Compression works by finding repetition, so random numbers repeat by accident only. Lossless JPEG squeezes out what predictability neighboring photosites offer, reaches roughly half, then runs out of room.
Canon took another route in CR3. Its C-RAW option throws a little away and halves files again. CR2 never offered that choice, so every CR2 you own is lossless.
Storage has grown faster than sensors. A 37MB photo sounded heavy in 2016 and barely registers now. Deleting raw files to free room is rarely worth what you give up, and a JPEG export is not a substitute for one.
Built on TIFF, never documented by Canon and not registered with IANA. Four bytes at the front say TIFF. Two bytes at offset 8 say Canon.
Nothing here helps you open a photo. It is on record for two reasons. CR2 is proprietary and Canon published no specification, so everything below came from people taking files apart. And the older version of this page filled its specification table with software names instead.
| Property | Value |
|---|---|
| Full name | Canon Raw version 2 |
| Published specification | None. Canon has never released one |
| Kind | A binary image file format, never text |
| Container | TIFF, little-endian |
| Signature | 49 49 2A 00 at offset 0, then CR at offset 8 |
| Version | Major 2, minor 0, in every CR2 written |
| Directories | Four, numbered 0 to 3, three of them previews |
| Compression | Lossless JPEG on the sensor data |
| Bit depth | 12 or 14 bits per photosite |
| Color layout | Bayer mosaic, RGGB order on Canon bodies |
| Media type | None registered with IANA. No Canon entry appears in the registry |
| Quoted in the wild | MIME image/x-canon-cr2, unregistered. That x- prefix marks a type nobody registered |
Sixteen bytes sit at the front of every CR2 file. First eight are plain TIFF and Canon added the next eight.
| Offset | Bytes | What it means |
|---|---|---|
| 0 | 49 49 | II, so numbers run little-endian |
| 2 | 2A 00 | 42, the number marking a TIFF file |
| 4 | 10 00 00 00 | Where directory 0 begins, which is byte 16 |
| 8 | 43 52 | CR, the two letters saying Canon |
| 10 | 02 | Major version, 2 |
| 11 | 00 | Minor version, 0 |
| 12 | Four bytes | Where directory 3 begins, holding your photograph |
Offsets 8 through 15 are the Canon part. TIFF leaves that space free, which is why any TIFF reader walks a CR2 happily and finds three previews sitting in it.
Canon documented none of this. Everything above was worked out by people reading files byte by byte, and their findings became the code that free software uses today.
That is also why raw support arrives camera by camera. Nobody can write CR2 support in general when nobody has published what CR2 is, so every new body means somebody buys one and works out what changed.
Two details trip up anyone parsing one. Canon cuts the sensor data into vertical slices, and a tag numbered 0xc640 says how wide they are. The width inside the lossless JPEG stream is half the real width, because two photosites travel side by side.
Two questions sort out most of what is left. Answer them in order.
Check that first. A .cr3 sitting in a folder of CR2 files explains most of these, and section 6 covers the rest.
Nothing is broken. Raw arrives undeveloped and waits for you. Section 5 lists three developers that cost nothing.
Sorting out a folder of camera files? Canon raw before 2004 covers the older bodies, and Adobe DNG files are where photos belong for the long term.
Shooting more than one brand? Sony ARW photo files, Nikon NEF raw photos and Fujifilm's RAF format work the same way and need the same care.
Editing what comes out? PSD files from Photoshop hold your layers. PDF documents are where prints and proofs end up, and TGA image files or PCX picture files turn up in older photo archives.
Stuck on your computer rather than your photo? Our Windows fixes and macOS guides cover the system side.
New to all of this? What a file format is covers the ground underneath, and our file format guides list the rest.
Found something here that does not match your own file? Send us the exact wording on screen and we will check it against the reference.