Image format

QOI

A small lossless codec for 8-bit RGB and RGBA images, designed for simple, fast implementations.

Convert QOI to

Choose a target format for your QOI images.

JPEGJPEGQOI → JPEG PNGPNGQOI → PNG WebPWebPQOI → WebP AVIFAVIFQOI → AVIF HEICHEICQOI → HEIC HEIFHEIFQOI → HEIF

All 21 conversions

GIFGIFQOI → GIFWith caveat TIFFTIFFQOI → TIFF BMPBMPQOI → BMP ICOICOQOI → ICO JPEG XLJPEG XLQOI → JPEG XL JPEG 2000JPEG 2000QOI → JPEG 2000 TGATGAQOI → TGA PCXPCXQOI → PCX PPMPPMQOI → PPM PGMPGMQOI → PGMWith caveat PBMPBMQOI → PBMWith caveat PAMPAMQOI → PAM HDRHDRQOI → HDR EXREXRQOI → EXR PDFPDFQOI → PDF

Marked paths may need steps such as flattening, rasterization, tone mapping or animation loss.

Convert to QOI

Choose a source format to convert to QOI.

JPEGJPEGJPEG → QOI PNGPNGPNG → QOI WebPWebPWebP → QOI AVIFAVIFAVIF → QOI HEICHEICHEIC → QOI HEIFHEIFHEIF → QOI

All 36 conversions

GIFGIFGIF → QOIWith caveat TIFFTIFFTIFF → QOI BMPBMPBMP → QOI SVGSVGSVG → QOI ICOICOICO → QOI JPEG XLJPEG XLJPEG XL → QOI JPEG 2000JPEG 2000JPEG 2000 → QOI TGATGATGA → QOI PCXPCXPCX → QOI PPMPPMPPM → QOI PGMPGMPGM → QOI PBMPBMPBM → QOI PAMPAMPAM → QOI HDRHDRHDR → QOIWith caveat EXREXREXR → QOIWith caveat PSDPSDPSD → QOIWith caveat PDFPDFPDF → QOIWith caveat DNGDNGDNG → QOI Canon CR2Canon CR2Canon CR2 → QOI Canon CR3Canon CR3Canon CR3 → QOI Canon CRWCanon CRWCanon CRW → QOI Nikon NEFNikon NEFNikon NEF → QOI Sony ARWSony ARWSony ARW → QOI Fujifilm RAFFujifilm RAFFujifilm RAF → QOI Olympus ORFOlympus ORFOlympus ORF → QOI Panasonic RW2Panasonic RW2Panasonic RW2 → QOI Pentax PEFPentax PEFPentax PEF → QOI Sigma X3FSigma X3FSigma X3F → QOI Kodak RAWKodak RAWKodak RAW → QOI Hasselblad 3FRHasselblad 3FRHasselblad 3FR → QOI

Marked paths may need steps such as flattening, rasterization, tone mapping or animation loss.

About QOI

Quite OK Image Format

Dominic Szablewski designed QOI as a deliberately small lossless raster format. It stores 8-bit RGB or RGBA pixels using a short header, a sequence of compact coding operations and an end marker. The specification prioritises implementation simplicity rather than a container full of optional media features.

The stream uses repeated pixels, small differences and a recent-pixel index to encode image data without changing its values. A colour-space flag distinguishes the specified sample interpretation, but there is no ICC-profile or Exif chunk system. Alpha is an ordinary fourth 8-bit channel when RGBA is selected; higher-bit-depth samples are not represented.

Use QOI for application-controlled image assets and intermediate storage when both ends implement it. It is not an animated format or a substitute for a layered master. Converting high-precision or metadata-rich sources to QOI needs deliberate reduction, even though the QOI coding step is lossless for its supported pixels.

Key capabilities

Compression: Lossless
Transparency: Yes
Animation: No
Extensions: .qoi
MIME type: No IANA-registered image type
Metadata: Colour-space flag
Best for: Application assets & simple decoding
Colour depth: 8 bits/sample

QOI preserves 8-bit RGB/RGBA samples losslessly. Reducing 16-bit data or discarding profiles and metadata before encoding is outside that guarantee.

History of QOI

QOI has a short, documented history centred on its creator’s 2021 proposal and the final compact specification.

2021
A small codec experiment
Dominic Szablewski develops a lossless image format aimed at fast encoding and decoding with a small implementation, rather than maximum compression at any cost.
2021-12-20
The final specification
The creator publishes the final QOI specification after discussion and refinement on GitHub. The concise document defines the exact valid stream structure.
QOI reference
An implementable specification
A reference encoder and decoder accompany the format. The specification retains a deliberately limited RGB/RGBA scope, making the implementation model more predictable than an open-ended multimedia container.

QOI compared

Different formats, different trade-offs. Choose for the image and the workflow.

PNG

QOI vs PNG

PNG preserves decoded pixels losslessly and can carry alpha. It is useful for transparent graphics and screenshots; it does not preserve editable document layers or camera sensor data, and photographic files can be large.

BMP

QOI vs BMP

BMP suits Windows bitmap interchange and simple pixel inspection. Uncompressed variants are easy to decode but can be large; palette, alpha and colour-profile behaviour depend on the header version.

TGA

QOI vs TGA

TGA offers straightforward raster storage, optional RLE and alpha for compatible asset pipelines. Its simplicity is useful for textures, while PNG offers a more explicitly standardised web and colour-metadata workflow.

WebP

QOI vs WebP

WebP combines lossy or lossless 8-bit image coding with alpha and animation. It is a web delivery option when those features matter; high-precision samples and editable source structures need another working format.

QOI FAQ

What does this format store?

How does compression affect quality?

QOI preserves 8-bit RGB/RGBA samples losslessly. Reducing 16-bit data or discarding profiles and metadata before encoding is outside that guarantee.

Does QOI store Exif or animation?

The published QOI format defines one image and a colour-space flag, not Exif chunks, ICC profiles or timed frames. Keep required metadata separately or use another container.

What should I check before opening the file?

The application needs a QOI decoder. The reference implementation helps integrate support; a .qoi extension does not make the file a browser-native PNG or JPEG.

What changes when I export to another format?

PNG can preserve decoded RGB/RGBA samples. JPEG discards alpha and adds lossy coding; GIF reduces colours. Conversion cannot restore metadata or precision that QOI never stored.

When is this format useful?

Sources

QOI