# Browser detection

**URL:** <https://forum.kirupa.com/t/browser-detection/211605>\
**Category:** Uncategorized\
**Created:** [January 3, 2007, 3:28pm UTC](https://forum.kirupa.com/t/browser-detection/211605 "2007-01-03T15:28:59Z")\
**Posts on this page:** 1\
**Page:** 1

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**Author:** ![acc](https://avatars.discourse-cdn.com/v4/letter/a/b38774/32.png) [@acc](https://forum.kirupa.com/u/acc)\
**Post date:** [January 3, 2007, 3:28pm UTC](https://forum.kirupa.com/t/browser-detection/211605/1 "2007-01-03T15:28:59Z")

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I have the chance to start from scratch with using CSS styles in our website and would like to know which major browsers should I detect for, (Internet Explorer, Firefox, Netscape, Opera, are some I can think of) and how far back in their versions should I test?

Also, should I have a different CSS file for Mac and Windows for each browser?

In the past I’ve used a javascript sniffer, but would like to know is there a better one in ASP that detects the browser and OS in order for me to include the proper CSS styles sheet?