For an objective evaluation of conferences, we need an official third party whihc evaluates all the conferences, thus producing a credible classification (A, B and C or impact factor calculus).
First of all, there is no “Impact Factor” for Conference Proceedings. Impact Factor concerns only journals included in Thomson Reuters Journal Citation Reports. Generally speaking, Conference Proceedings papers would be rated as having “lower quality” as compared to other “higher quality” articles published in refereed international journals that are included in “Thomson Reuters Journal Citation Reports” that can be found through this link:
However, Conference Proceeding can be ranked in Thomson Reuters (as stated above by Miloš Jovanović) using “Conference Proceeding Citation Index” (so, there is no Impact Factor). You can find out useful information about this and the selection process through this link:
Just a short answer that might help: Thomson Reuters offers the Conference Proceedings Citation Index- Science (CPCI-S) and the Conference Proceedings Citation Index- Social Science & Humanities (CPCI-SSH). You could use these as a basis for a ranking (e.g. by using the impact factor). I hope this helps a little.
First of all, there is no “Impact Factor” for Conference Proceedings. Impact Factor concerns only journals included in Thomson Reuters Journal Citation Reports. Generally speaking, Conference Proceedings papers would be rated as having “lower quality” as compared to other “higher quality” articles published in refereed international journals that are included in “Thomson Reuters Journal Citation Reports” that can be found through this link:
However, Conference Proceeding can be ranked in Thomson Reuters (as stated above by Miloš Jovanović) using “Conference Proceeding Citation Index” (so, there is no Impact Factor). You can find out useful information about this and the selection process through this link:
The first link is a web page that includes a list of ranked conferences and journals, while the second link is a file that includes a list of journals taged by impact factors according to some measures.
you can also take a look to a more recent intiative by two Italian and a Spanish Computer Science societies where they have gathered and combined three different conference quality rankings :
I would recommend this website http://www.guide2research.com/. It provides updated rankings and ratings (important ones) for all the conference and journals. I found it quite relevant to my field of research (Computer Vision, Machine Learning). It includes different independent accreditation and also has good filtering options, so you can set different parameters to check the reputation of the particular conference or journal.
You should be aware that most of conferences appear to be scholarly conferences, but are in reality an exploitative means used by predatory publishers and conference organizers to make money in the form of registration fees.