Why not rename .bmp to .ico

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Why not rename .bmp to .ico

A Windows bitmap image (.bmp) is not the same as a Windows icon (.ico).

The .ico file format contains several images and while the individual images may be stored in roughly the same way as a .bmp file, there is an important header at the beginning of the .ico file, which is missing in a .bmp file.

It is a widespread myth that it is possible to safely rename .bmp files to .ico files, but it is not true. While it may occasionally work, this is purely a coincidence. Applications, which are able to read both .ico files and .bmp files, will sometimes ignore the extension and use the file despite the wrong extension (Firefox is a typical example).

Particularly web masters trying to create a favicon for their web site are prone to take this shortcut and then wonder why isn't their favicon.ico working in Internet Explorer.

To convert .bmp to .ico, use a dedicated tool:

Recent comments

user icon Anonymous on March 8th 2016

i changed out the ext name from the dot(.) rename .bmp to .ico the dot(.) must be changed as well in all windows from Xp to win 8 win is different first you need to find how to un-hide the file extension first which i am still looking for

user icon Anonymous on June 12th


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