« on: December 21, 2012, 07:57:21 PM »
I suppose you use a different working color space (like AdobeRGB). Even if your setup is correct, make sure you export in sRGB. Some browsers (Chrome is one example) ignore embedded color profiles and always assume sRGB, and some websites seem to ignore or remove color profiles altogether, especially the ones that process the uploaded files to create different sizes (like flickr).
I'll second this. Unless you specifically know your end-user(s) will be needing AdobeRGB (like if they are printing), then export as JPG/PNG with sRGB, it's just so much easier and well supported.