NEF to AVIF Converter

Encoding: the NEF uses uncompressed, lossless compressed, lossy compressed, or High Efficiency on recent Z bodies; AVIF uses lossy or lossless AV1 intra-frame coding, and the download is an AVIF encoded with libavif (AV1) compiled to WebAssembly, at the quality you choose.

Bit depth: 12 or 14 bits per channel in the NEF; AVIF allows 8, 10 or 12 bits per channel, and the AVIF written here has 8 bits 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; AVIF supports YUV 4:4:4 or 4:2:0 with BT.709, Display P3 or BT.2020 primaries, HDR curves possible, written here as 8-bit sRGB.

Metadata: the NEF can carry EXIF and Nikon maker notes, partly encrypted, plus a thumbnail and a larger preview; AVIF can carry EXIF, XMP and ICC stored as HEIF items, but nothing is copied across.

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.

AVIF uses the AV1 video codec for still images. It is the most efficient widely supported format, often half the size of JPEG, with HDR, wide colour and transparency, but encoding is slow.

An AVIF is a HEIF file, the same ISO base media boxes as MP4, with the brand 'avif'. The picture is an AV1 key frame stored as an image item, and its size, colour and pixel layout are item properties.

AVIF is the better choice for maximum compression on modern websites, while NEF suits editing Nikon photos in a raw developer.

AVIF strengths: Often 50% smaller than JPEG; Excellent at low quality settings; Transparency, HDR and 10/12-bit colour. Drawbacks to weigh: Slow to encode, especially on phones; Not supported by some older software; Can smooth away fine texture at low quality.