Regex JavaScript image file extension [closed]

Could you explain the purpose?

Anyway here's one assuming you support few image types.

(/\.(gif|jpe?g|tiff?|png|webp|bmp)$/i).test(filename)

I have put the whole regular expression within parentheses () so as to disambiguate between the slash (/) operator and RegExp object. See JSLint for more details.

Here's the raw regex as well.

/\.(gif|jpe?g|tiff?|png|webp|bmp)$/i

This Regex also assumes that you're including the dot before the extension. Remove the \. if you're not.