What Is a DNG File? The DNG Format, Explained With 10 Real Files

Published November 5, 2026 · Daniel Tello · RevelRaw

Two files can share the .dng extension and hold very different data. Short on time? Open a DNG on a Mac or turn it into a JPG.

The DNG file format at a glance

Adobe's 2004 release gave two reasons for creating DNG: raw files "vary between manufacturers and individual cameras", and, as Adobe's Bryan Lamkin put it, "nobody can be sure that today's raw formats will be supported ten years from now."

Older pages that call DNG "not an ISO standard" were right until 2026. ISO sells its text, while Adobe's spec stays a free download under a royalty-free patent license with conditions. That makes DNG publicly documented, which is different from open source.

Got a .DNG that won't open? The step-by-step is in How to Open DNG Files on a Mac, or open it in RevelRaw now, free.

What is a DNG file made of?

The image data comes in two forms, and which one you have decides what the file can do later:

• Mosaic. One color value per pixel (the spec's color filter array, or CFA). It still needs demosaicing, where software works out full color for every pixel.
• Demosaiced. Color is already worked out for every pixel. The Library of Congress says this is "sometimes called Linear DNG"; Adobe's converter says "Linear (demosaiced)".

A DNG can also carry EXIF, IPTC and XMP metadata, private maker data and embedded previews. Previews are optional: the spec "recommends, but does not require" a low-resolution thumbnail. Three extras:

• A checksum. It's optional, and three of our 10 files have one: the two Adobe-written files and the Pixel 8 Pro. We found no documented case of one catching silent corruption.
• The original raw file. Embedding it "can double the file size", Martin Evening wrote in 2015.
• Your edits. Lightroom can save them in the DNG as metadata. Martin Evening, writing on Adobe's blog, says saved edits slow backups because the whole DNG is recopied.

What is DNG in practice? 10 real files compared

We hand-picked these 10 from the raw.pixls.us archive's 257 CC0 DNGs to span makers and DNG types, not as a market survey, so the spread is partly designed in and no count is a market share.

MB is 1,000,000 bytes (our sample page uses binary MB). MB per MP is the whole file over raw megapixels, previews included, not a compression ratio. The 7D Mark II's 1.85 counts both images; its mosaic alone is 1.16. Each version describes that one file, not what the maker's current models write. Bit depth is what each file states: the 7D Mark II, Leica and Pixel values sit inside a 14-bit range. "Lossless JPEG" covers the compression step only and doesn't mean untouched sensor readings: the Pixel file lists its software as HDR+. We inferred the Samsung's "demosaiced" from its metadata.

What it means if you're holding a DNG

Across the 10 files we inspected on November 5, 2026:

• The extension doesn't say what's inside. Cloudinary sorts DNGs by where they came from; our table shows what's inside, and that in-camera files can be demosaiced too. Check yours with our free EXIF viewer.
• Versions vary. The 10 files span four DNG versions, 1.2 through 1.7. The number the spec tells apps to check is the backward version: the 1.7 Lightroom file declares 1.1, consistent with the spec's rule, which asks for at least 1.7 when the main image uses JPEG XL; this file's doesn't.
• File size isn't quality. File size per megapixel ran from 0.28 MB to 3.14 MB. That 11-fold spread comes from the one lossy file, a rarity we picked on purpose; without it the range is 0.90 to 3.14, about 3.5-fold. The two heaviest files per megapixel are the lossless demosaiced ones, which store three 12-bit channels per pixel; the lightest lossless file stores one channel, tagged 16-bit.
• The preview may be tiny. Six of 10 files embed a preview at or very near full width (99.7% or more); on the other four the JPEG is at most 31.4% of full width, as low as 960 × 720. On the four files we tested, Quick Look thumbnails used the embedded JPEG when it was at least as large as the size drawn, and the raw data otherwise.
• It may hold your location. Four of 10 carry GPS coordinates: two phones and two drone cameras.

What's the difference between two DNG files?

The Pixel 8 Pro file is a 45.10 MB mosaic, tagged 16-bit. The lossy Adobe file began as a Canon 5D Mark III raw and ended at 6.19 MB. A DNG whose main image uses lossy JPEG holds 8-bit linear data, so from an ordinary color-filter camera it is already demosaiced. With the Pixel file your raw editor still does that step. With the lossy file it's done, at 8 bits, and as Adobe says, "Mosaic image data can be converted to linear data, but the reverse is not possible." In one Fstoppers test (2024), a different lossy DNG showed artifacts under heavy shadow lifts.

Lightroom's DNG 1.7 file is two images in one: a lossless JPEG mosaic taking 62.8% of the file and a JPEG XL Enhanced image taking 36.1%. That's the Canon 7D Mark II row, and its Enhanced image, a denoised version, is tagged "Adobe Denoise 1 Amount 50".

Which cameras and phones shoot DNG?

Apple says ProRAW "uses the industry standard digital negative (DNG) file format", on iPhone 12 Pro and later Pro models. Samsung says Expert RAW saves "Linear DNG 16-bit". The Leica M11, Ricoh GR IV, Sigma fp and DJI Mavic 4 Pro also write DNG, and the Pentax K-3 Mark III offers DNG alongside PEF.

Canon, Nikon, Sony and Fujifilm use their own raw formats (CR3, NEF, ARW, RAF). Canon told The Verge in April 2025 that its format lets it add proprietary information without being restricted by the standardization; Sony cited performance tuned to sensor and processor. Nikon and Fujifilm did not answer by publication. Hasselblad's X2D II 100C writes 3FR. The Hasselblad DNG in our sample came from a Hasselblad-branded camera on a DJI drone.

Why doesn't a DNG work the same everywhere?

Calling DNG "universal" goes too far. It is widely supported in its common form, and critics' claim that other software can't read it is out of date for ordinary mosaic files. The spec tells apps to refuse a file that says it needs a newer DNG version than they were built for. macOS's built-in RAW decoder decoded all 10 files, four from cameras absent from its RAW list.

Edits don't always travel. Capture One's support page says it does not support adjustments from other apps embedded in a DNG.

Is the DNG format compressed, and is it really 20% smaller?

Adobe's DNG page, answering whether DNG files lose quality, says: "Unlike file types such as JPEG, which compress files, there's no compression involved in creating a DNG file, so there's no process that might cut out important data within the image itself." The likely intent is "no lossy compression by default", which is defensible. Still, nine of the 10 DNGs we measured use compressed main images: eight lossless JPEG, one lossy JPEG. The page also says twice that a DNG "stores uncompressed image data". Our Hasselblad file does. Alexander Kunz noted in 2022 that cameras writing DNG "often write uncompressed data (DJI, Leica, probably others too)", citing a 12 MP DJI file at about 25 MB and a 40 MP Leica file at 85 MB. Our Leica and DJI Mavic 3 Pro files use lossless JPEG, so it isn't every file.

Adobe's converter defaults to lossless compression, but lossy options exist, so check the setting. No source we found shows lossless conversion changing the pixels, and we ran no conversions ourselves.

Adobe also says a DNG is "around 20% smaller" or "generally 15-20% smaller". That's roughly right for some lossless raws, but neither page gives a test, and it says nothing about a file born DNG. These forum and blog reports aren't our figures, and we found no controlled benchmark:

Bay and Kotz state lossless output; the others state no setting, and lossless is the converter's default. The a7 V and Nikon percentages are arithmetic on posted sizes.

Should you convert to DNG?

If your camera writes DNG, use it. Don't convert native RAW by default. Never convert and delete the originals. Convert when software can't read your files, or to keep an added copy, and test your own files first.

The case for is real. Uncompressed raw on a body with no lossless option shrinks by about half in the a7R IV reports, and uncompressed Hasselblad X2D 3FR by 23% to 32% (Lloyd Chambers, 2022). Stephen Bay says he has been "converting them into DNG and deleting the original files". The U.S. National Archives (NARA) rates DNG 1.7 Low risk and rates Canon CR3, Nikon NEF, Sony ARW and FujiFilm RAW Moderate, with the stated plan "Transform to DNG". And sometimes DNG is what opens: one user reports Nikon Z6III HE* NEFs failing in a darktable nightly on Linux while DNG Converter output worked.

The case against.

• Adobe's converter "may, in some cases, ignore some of this proprietary metadata". An Adobe representative told Lloyd Chambers in 2022 that lossless and uncompressed DNGs keep the MakerNotes (camera makers' private data) Adobe knows about, though it is "impossible for us to be 100% certain", and "we deliberately exclude the private MakerNotes from lossy-compressed DNGs".
• Conversion is one-way unless you embed the original, which cancels the saving.
• Adobe's blog warned in 2015 that you "lose the ability to process DNG files using the manufacturer's dedicated raw processing software, unless you choose to embed the original raw".
• Sony told The Verge its format lets it offer features such as Composite RAW and Pixel Shift Multi in its own software, and Lloyd Chambers reported in 2022 that "the Sony software doesn't work with DNG".

The trade-off. The space saving only exists if you delete the originals, so keeping them gives up size as a reason to convert. "Never convert and delete" is our advice, not a finding: no source we found shows pixel loss in lossless mode, and embedding the original removes the risk while cancelling the saving. The strongest policy fact against convert-and-delete is NARA's general format policy, not specific to camera raw, of "retaining the original format files in low-access storage".

Adobe DNG Converter is free (version 18.7, September 2026; Adobe lists system requirements). Convert a dozen files, compare sizes, and open them in every app you use.

Can a Mac open DNG files?

Yes, macOS reads DNG itself: Apple lists "basic support" for DNG from "these and other cameras". The steps and fixes are in our Mac guide to DNG files.

RevelRaw reads DNG. That includes JPEG-XL-compressed ProRAW from iPhone 16 Pro and later on macOS 26 or later, based on one real file we opened; we didn't run RevelRaw on the 10 test files. Your photos stay on your Mac, and it can remove GPS on export. iPhone shooters can start with editing ProRAW on a Mac.

FAQ

Is DNG better than JPEG?

It depends what's in the DNG. Nine of the 10 hand-picked DNGs in RevelRaw's November 2026 test have main images tagged 12 to 16-bit, against 8-bit JPEG previews, so they hold far more editing data; the lossy DNG is the exception at 8-bit. The cost is size: Apple's 2024 figures put ProRAW at 10 to 12 times HEIF or JPEG. A JPEG is ready to share.

What program opens a DNG file?

macOS has built-in DNG support, Lightroom and Photoshop work with DNG, Adobe says hundreds of software makers support it, and RevelRaw reads it. Support varies by file type: darktable 5.6.2's notes list ProRAW and DNG 1.7 JPEG XL under missing compression mode support, alongside native modes such as Nikon high efficiency NEFs. Our guide to opening a DNG on your Mac has the steps.

Why are my photos being saved as DNG?

A raw setting is the likely cause: ProRAW on an iPhone, Expert RAW on a Samsung, or a raw option on a drone or a Pixel (Tim Bray reports this). On an iPhone, go to Settings > Camera > Formats to turn it off.

Can I convert a DNG file to jpg?

Yes. macOS's built-in decoder produced a JPEG from all 10 hand-picked DNGs in RevelRaw's November 2026 test, and RevelRaw exports JPEG. Adobe DNG Converter won't help: it doesn't make JPEG files. Our DNG to JPG walkthrough has the steps. Keep the DNG afterwards as your master.

Is DNG a RAW file?

Yes, but not always untouched raw. In RevelRaw's November 2026 test of 10 hand-picked DNGs, seven main images are mosaics, with color still to be worked out, and three are demosaiced, with color already worked out, and Apple says "the system demosaics and partially processes Apple ProRAW photos."

How can I tell what kind of DNG I have?

Drop it on our free EXIF viewer, open All tags and find the block with SubfileType 0, the main image; in eight of the 10 files in RevelRaw's test the first block is only a preview. There, Compression reads "JPEG (7)" for lossless, "Uncompressed (1)" for none and "Lossy JPEG (DNG) (34892)" for lossy, and PhotometricInterpretation starts "Color filter array" for a mosaic or "Linear raw" for demosaiced.

Related reading: How big is a RAW file? · RAW vs JPEG · All RAW formats · CR3 · NEF · ARW