About ARW Files
Sony RAW ARW
ARW is Sony Alpha RAW format for professional and mirrorless cameras.
Family
Raster & Vector Images
Extension
.arw
MIME Type
image/x-sony-arw
Can Use As
HOW ARW
CAME TO BE.
ARW — Alpha RAW — is the native raw format of every Sony Alpha camera since the Alpha 100 (2006), when Sony inherited Konica Minolta’s camera division and continued their SR2/MRW lineage under a new extension. ARW is a TIFF/EP variant, the same structural family as CR2 and NEF, with Sony-specific makernotes for lens data, creative styles, and the Bionz processor’s noise-reduction settings.
Sony Alpha bodies — especially the full-frame A7/A9/A1 series — account for a massive share of professional wedding, event, and wildlife photography since 2015. Every ARW file from that explosion sits on someone’s NAS. The format has remained stable across four Bionz generations, though Sony regularly tweaks the internal sensor data layout with each new camera, forcing raw processors to ship matching profile updates.
CURIOSITIES &
TRIVIA.
ARW descends from Konica Minolta's SR2/MRW format — Sony inherited the codebase when it bought the camera division in 2006.
Sony Alpha bodies shot over 50% of all professional mirrorless weddings between 2018 and 2024 — a massive volume of ARW files.
Sony's "Pixel Shift Multi Shooting" bodies (A7R III onward) produce ARW sequences that third-party tools combine into 240 MP composites.
Every new Sony body ships with a sensor data layout tweak — which is why Lightroom needs an update whenever you buy a new Sony.
The A1 records 14-bit ARW at 30 frames per second in full resolution — 800+ MB per burst.
STRENGTHS &
LIMITATIONS.
Strengths
- Full 14-bit sensor data on flagship bodies.
- Rich Sony metadata (Creative Style, DRO, Focus Magnifier).
- Supported by every major raw processor.
- Lossless compression available on modern bodies.
Limitations
- Proprietary — new Sony body launch = Lightroom update required.
- Lossy compression was the only option on many older bodies (visible banding in highlights).
- File sizes are huge on 50+ MP bodies.
- Some ARW variants use 16-bit layout that breaks older third-party tools.
Typical Sizes & Weights
24 MP ARW (A7 III, A7C)
25-45 MB
42 MP ARW (A7R III)
50-90 MB
61 MP ARW (A7R IV, A7R V)
75-130 MB
Technical Specifications
- MIME type
- image/x-sony-arw
- Extension
- .arw
- Container
- TIFF/EP with Sony MakerNote tags
- Bit depth
- 14-bit (flagship); 12-bit (entry)
- Compression
- Uncompressed, Lossless, Lossy
CONVERT FROM
ARW
Common Use Cases
Sony mirrorless photography
Related Formats
Popular comparisons
ARW vs JPG
Differences, file size, and when to choose each format.
ARW vs PNG
Differences, file size, and when to choose each format.
ARW vs WEBP
Differences, file size, and when to choose each format.
ARW vs AVIF
Differences, file size, and when to choose each format.
ARW vs GIF
Differences, file size, and when to choose each format.
ARW vs BMP
Differences, file size, and when to choose each format.
Popular ARW conversions
The most-requested destinations when starting from ARW.
Frequently Asked Questions about ARW
Frequently Asked Questions
ARW (Sony RAW ARW) is an image format used to store raster graphics — a two-dimensional grid of pixels describing a picture. It is part of the raster & vector images family and designed around a specific trade-off between file size, visual fidelity, and feature support (transparency, colour depth, compression type). Photographers, web designers, and content creators choose ARW when its particular strengths match the publishing target.
Most desktop photo viewers (Windows Photos, macOS Preview, GIMP, Photoshop, Affinity Photo) open ARW natively. On mobile, iOS Photos and Google Photos display ARW in the gallery when supported by the OS. If the format is rare or new, convert to JPG or PNG first — both are universally readable — using our ARW to JPG or ARW to PNG converter.
Upload the ARW to KaijuConverter and pick a target format (JPG, PNG, WebP, HEIC, TIFF, BMP, SVG, PDF). The conversion runs in the browser via ImageMagick and returns a download in seconds. No account or installation required; both input and output delete automatically within two hours.
It depends on the task. JPG is the smallest file size for photographs; PNG is lossless with transparency; ARW has its own niche that may favour colour depth, animation, or encoding efficiency over one or both of those. For the final web publish, test all three and measure file size plus visible quality on real content.