The short answer
- CR2 is a Canon RAW raster image format that preserves minimally processed camera-sensor data and imaging metadata, but requires compatible RAW-processing software for normal rendering.
- Keep the original CR2, then open a working copy in an updated RAW processor that explicitly supports CR2. Canon identifies Digital Photo Professional as suitable software for displaying, adjusting, and converting its RAW images. On Windows or macOS, select the file through the processor's Open command. On a phone, first confirm that the chosen RAW app supports CR2; proprietary RAW compatibility varies by software. Convert a copy to JPEG or TIFF when an ordinary viewer, printer, or recipient cannot use CR2.
- CR2 format documentation does not describe scripts, macros, or other active content, but an untrusted CR2 still passes through a complex RAW decoder. NIST has documented a crafted-file heap buffer overflow in a LibRaw decoding path with high confidentiality, integrity, and availability impact. Use a fully updated decoder, limit processing resources, and isolate unknown files. Successful rendering does not establish that an image or its source is trustworthy.
CR2 file: how to open, assess, and convert Canon RAW images
Canon created and supports Canon RAW Version 2. A CR2 file stores binary sampled-image data captured by the camera sensor with relatively little in-camera processing, plus metadata needed to interpret settings such as white balance. Canon cameras beyond the EOS DSLR range can create it; the PowerShot S90, for example, records .CR2 RAW images.
Convert a copy rather than replacing the original CR2. JPEG is convenient for ordinary viewing and delivery, but its processing and compression are irreversible and cannot preserve the original sensor data or full adjustment range. TIFF is a preferred digital-photograph format in the Library of Congress recommendations, but a converted TIFF still does not replace the original RAW data. RAW processing can produce multiple versions with different white balance or Picture Style settings while leaving the CR2 unchanged.
How to open it
Keep the original CR2, then open a working copy in an updated RAW processor that explicitly supports CR2. Canon identifies Digital Photo Professional as suitable software for displaying, adjusting, and converting its RAW images. On Windows or macOS, select the file through the processor's Open command. On a phone, first confirm that the chosen RAW app supports CR2; proprietary RAW compatibility varies by software. Convert a copy to JPEG or TIFF when an ordinary viewer, printer, or recipient cannot use CR2.
Keep the original CR2, then open a working copy in an updated RAW processor that explicitly supports CR2. Canon identifies Digital Photo Professional as suitable software for displaying, adjusting, and converting its RAW images. On Windows or macOS, select the file through the processor's Open command. On a phone, first confirm that the chosen RAW app supports CR2; proprietary RAW compatibility varies by software. Convert a copy to JPEG or TIFF when an ordinary viewer, printer, or recipient cannot use CR2.
Convert a copy rather than replacing the original CR2. JPEG is convenient for ordinary viewing and delivery, but its processing and compression are irreversible and cannot preserve the original sensor data or full adjustment range. TIFF is a preferred digital-photograph format in the Library of Congress recommendations, but a converted TIFF still does not replace the original RAW data. RAW processing can produce multiple versions with different white balance or Picture Style settings while leaving the CR2 unchanged.
File safety
CR2 format documentation does not describe scripts, macros, or other active content, but an untrusted CR2 still passes through a complex RAW decoder. NIST has documented a crafted-file heap buffer overflow in a LibRaw decoding path with high confidentiality, integrity, and availability impact. Use a fully updated decoder, limit processing resources, and isolate unknown files. Successful rendering does not establish that an image or its source is trustworthy.
An unknown sender, a name ending in two extensions, or contents that do not match the extension — check before you open it.
Converting it
Convert a copy rather than replacing the original CR2. JPEG is convenient for ordinary viewing and delivery, but its processing and compression are irreversible and cannot preserve the original sensor data or full adjustment range. TIFF is a preferred digital-photograph format in the Library of Congress recommendations, but a converted TIFF still does not replace the original RAW data. RAW processing can produce multiple versions with different white balance or Picture Style settings while leaving the CR2 unchanged.
Convert a copy, never the original, then compare quality, metadata, and layout against what you started with.
Common questions
What is a CR2 file format and what does it contain?
CR2 is Canon RAW Version 2, a raster image format containing minimally processed camera-sensor samples and metadata used to interpret imaging parameters such as white balance.
How do I open a CR2 file with Canon Digital Photo Professional?
Preserve the original, open a working copy in Digital Photo Professional, and use its RAW controls to display or adjust the image. Export JPEG or TIFF when you need a conventional image.
How do I open a CR2 file on Windows?
Use an updated Windows RAW processor that explicitly lists CR2 support. Open a copy of the file, then export JPEG or TIFF if standard Windows viewers cannot render it.
How do I open a CR2 file on a Mac?
Use a current macOS RAW processor with explicit CR2 support. Because camera RAW formats are proprietary and software-dependent, confirm support before relying on the rendered result.
How do I open a CR2 file on a phone?
Choose a mobile RAW app that explicitly supports CR2 and open a copy. If support is unavailable, convert the CR2 on a compatible desktop processor and transfer a JPEG or TIFF copy.
Why will my CR2 file not open or render correctly?
The processor may lack support for that CR2 variant, the decoder may be outdated, or the file may be damaged. Preserve the original, try an updated CR2-compatible processor, and avoid repeatedly overwriting the file.
Should I use CR2 or JPEG for a Canon photo?
Use CR2 when retaining sensor data and later white-balance or Picture Style adjustment matters. Use JPEG for ordinary viewing and delivery, but keep the CR2 because JPEG processing and compression are irreversible.
Does converting CR2 to JPG lose quality or RAW data?
Yes, JPEG conversion discards the original RAW sensor representation and reduces later adjustment range. Canon notes that JPEG processing and compression cannot be reversed, so retain the CR2.
Can I convert CR2 to TIFF and keep the original image quality?
A carefully generated TIFF is suitable for conventional use and is among the Library of Congress preferred digital-photo formats, but it does not preserve the CR2's original RAW sensor data. Keep both files.
Is a CR2 RAW file safe to open?
CR2 has no documented script or macro content, but malformed files can target RAW-decoder vulnerabilities. Open untrusted CR2 files only with an updated decoder, constrained resources, and isolation where appropriate.
Is CR2 suitable for long-term photo storage and compatibility?
Keep the original CR2, but do not rely on it as the only accessible copy. The format is proprietary and software-dependent; the Library of Congress accepts camera RAW but prefers formats including TIFF, JPEG 2000, PNG, and JPEG/JFIF for digital photographs.
Related formats
Sources
PRONOM: Canon RAW, Version 2.0 (fmt/592) · The National Archives (UK) PRONOM format registry
Camera Raw Formats (Group Description) · Library of Congress Sustainability of Digital Formats
PowerShot S90 Camera User Guide · Canon Europe official product documentation
EOS 450D Instruction Manual · Canon Europe official product documentation
Recommended Formats Statement – Summary of Digital Format Preferences · Library of Congress
LibRaw: Library for Reading and Processing RAW Digicam Images · Official LibRaw source repository
CVE-2026-21413 Detail · NIST National Vulnerability Database