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HomeFormats.ICOFull

What is a .ICO file?

ICO is the Windows icon format, storing one or more small images at several sizes for app icons and favicons.

Did you know
  • The ICO format dates back to Windows 1.0 in 1985.
  • An ICO file can pack several images at different sizes and colour depths so Windows can pick the right one for each context.
  • Lower colour-depth icons store transparency using a separate 1-bit “AND mask” alongside the colour data.
  • Since Windows Vista, large 256-pixel icons can be stored as embedded PNG data to keep the file small.
  • Analyser spots a .ICO file by its signature bytes 00 00 01 00.
What Analyser shows you
View EXIF, GPS, camera settings, histograms, dominant colours, OCR text, and AI-generation markers in JPG, PNG, HEIC, WebP, GIF, BMP, TIFF, AVIF and JPEG XL images. Detects computational-photo wrappers (Apple Live Photo, Google and Samsung Motion Photo, Ultra HDR gain maps), opens THM movie-thumbnail files, and extracts every embedded image from multi-image files - all sizes in an ICO, both halves of an MPO stereo pair, and every page of a multi-page TIFF.
Open a .ICO file
Drag a .ICO file onto the Analyser home page (or tap to pick one). It opens entirely in your browser - nothing is uploaded, there is no account, and it works offline once installed.
Related formats
.JPG · .JPEG · .JIF · .JFIF · .PNG · .GIF · .WebP · .HEIC · .HEIF · .BMP · .TIFF · .AVIF · .JXL · .MPO · .THM. See all supported file types.