NEF to EXR Converter
Convert NEF to EXR in your browser. The largest embedded JPEG is converted; older bodies sometimes stored only a reduced preview, which then sets the output size. No raw development happens here. You get a ZIP-compressed OpenEXR with 16-bit half-float channels, the 8-bit sRGB values converted to linear light. Nothing is uploaded.
- Processed locally
- No upload, no wait
- No sign-up
- No watermark
Drop images here
or choose files · paste with Ctrl/⌘ V
RAW expected · other image formats also work
How to use NEF to EXR
- 1
Add your NEF files: drop them here, choose them, or paste from the clipboard.
- 2
There is nothing to tune: the EXR is written losslessly. Resizing and rotating are under More options if you need them.
- 3
Click Convert. Each file is decoded and encoded in a background thread on this device.
- 4
Download the .exr files one at a time or together as a ZIP.
Why use Aback Images for nef to exr
Where the EXR goes next
EXR opens in Nuke, Blender, Houdini, After Effects, DaVinci Resolve, Photoshop, Krita and OpenImageIO.
EXR next to NEF
The EXR holds the camera preview's pixels with lossless compression: usually smaller than a 20 to 60 MB raw file, though far larger than a JPEG of the same photo.
No new artefacts
The preview inside the NEF is a camera JPEG; the EXR stores its decoded pixels losslessly, so this step adds no compression damage of its own.
Processed on your device
Your images are decoded, edited and encoded inside this browser tab by Web Workers. Nothing is uploaded to a server.
NEF vs EXR
What changes from NEF to EXR
Encoding: the NEF uses uncompressed, lossless compressed, lossy compressed, or High Efficiency on recent Z bodies; EXR uses none, RLE, ZIP, PIZ, PXR24, B44 or DWA, chosen per file, and the download is a ZIP-compressed OpenEXR with 16-bit half-float channels, the 8-bit sRGB values converted to linear light.
Bit depth: 12 or 14 bits per channel in the NEF; EXR allows 16-bit half or 32-bit floating point per channel, and the EXR written here has 16-bit half float per channel. The sensor's 12 or 14 bits are not used: the 8-bit camera preview is converted.
Colour: camera RGB from a Bayer mosaic in the NEF; EXR supports scene-linear RGB, often ACEScg or linear Rec.709, written here as linear-light RGB.
Metadata: the NEF can carry EXIF and Nikon maker notes, partly encrypted, plus a thumbnail and a larger preview; EXR can carry named header attributes such as chromaticities, timecode and camera data, but nothing is copied across.
About NEF
NEF is the raw format of Nikon cameras, from the D1 to the current Z series. It stores 12 or 14-bit sensor data, uncompressed or compressed, with a JPEG preview the camera renders using its Picture Control.
NEF is TIFF-based: the first directory usually holds a small thumbnail, and sub-directories hold the sensor data and, on current bodies, a full-size JPEG preview. Nikon's maker notes are a TIFF structure of their own, and since the D2X their white-balance block is encrypted with a key derived from the camera's serial number and shutter count.
NEF files usually come from Nikon DSLRs (D-series) and Z-series mirrorless cameras.
About EXR
OpenEXR is the high dynamic range format of film visual effects. It stores half or full floating-point channels in linear light, plus any extra render passes, and is the working format of compositing pipelines.
An EXR starts with the magic number 76 2F 31 01 and a version field, then a header of named, typed attributes (channels, compression, dataWindow, displayWindow) and a table of offsets to scanline or tile blocks.
When converting NEF to EXR makes sense
EXR is the better choice for visual effects, compositing and 3D render output, while NEF suits editing Nikon photos in a raw developer.
EXR strengths: True high dynamic range in linear light; Any number of channels and render passes; Lossless compression options. Drawbacks to weigh: Needs tone mapping to look right on a normal screen; Very large files; No browser or phone support.
Limitations
- Nikon's lossy compressed NEF mode discards some sensor data in camera; the preview used here is not affected.
- No range is added: the EXR holds the 8-bit picture in linear light, and nothing in it is brighter than the original white.
- Compositing and 3D software read the EXR as linear light, the convention for the format, so it displays correctly there.
- The file holds colour and, when the image has transparency, an alpha channel; there are no extra render passes.
More conversions
Related tools
Convert EXR to NEF in your browser, saved as a Linear DNG, the raw file every NEF editor also opens. Batch, private, no uploads.
Convert NEF to JPG in your browser, made from the full-size preview your Nikon camera stored in the file. Batch, private, no uploads.
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Resize to exact pixels, a percentage or a longest side, with Lanczos3 and Magic Kernel resampling. Batch ready.
Strip EXIF, GPS, XMP, IPTC and comments losslessly. Pixels are never re-encoded for JPG, PNG and WebP.
Convert between 34 image formats in bulk: HEIC, WebP, AVIF, JPEG XL, PNG, JPG, GIF, TIFF, SVG, ICO, PSD, RAW and more.
Frequently asked questions
Does converting NEF to EXR lose quality?
EXR is written losslessly, so the pixels are stored exactly as decoded. Those pixels come from the camera's JPEG preview, so its compression stays, but nothing new is lost. The sensor's 12 or 14 bits are not used: the 8-bit camera preview is converted.
Does saving as EXR add dynamic range?
No. The values come from an 8-bit image, converted to linear light so compositing software displays them correctly, but nothing brighter than the original white is invented. The file is ready to use as a plate or texture in an EXR pipeline.
Which apps open EXR files?
Nuke, Blender, Houdini, After Effects, DaVinci Resolve, Photoshop, Krita and OpenImageIO. It does not open in web browsers.
Are my images uploaded anywhere?
No. Processing happens inside your browser with WebAssembly and Web Workers. The site only downloads the app code and codecs; your files never leave your device. You can confirm this with the live upload counter on the tool, or in your browser's network panel.
Can I process many files at once?
Yes. Drop a whole selection or folder. Files are processed in parallel on several worker threads, each result can be downloaded on its own, and everything can be saved as one ZIP.
Is it free? Is there a file limit or watermark?
It is free with no account, no watermark and no daily limit. The only limit is your device's memory: very large images (over roughly 100 megapixels) may be refused to keep the tab from crashing.