It is regarded the toughest exam primarily due to its selectivity. From approximately 500K about 10K get in. Thats an acceptance ratio of approximately 2% beating majority of other universities by a mile!
Despite this it isn’t the most selective exam in the world. The UPSC examination for Indian Administrative Services has an acceptance ratio of 0.025%. Most of the National Olympiads (here in India) have an acceptance ratio (acceptance in international team) of 0.02 % (5 out of 30K). Tshingua university has an acceptance ratio of 0.035% (SOURCE: College confidential).
Though selectivity is not exactly a fair metric. A lot of those 500K students are not serious about JEE and majority of them will be giving it for the heck of it. Hence the 2% acceptance ratio is a misguided figure for judging.
(though I have to agree I do not know the number of serious candidates among those applying to other universities. But I’ll think that the percentage is greater than JEE since the financial costs are higher to weed a lot of non serious candidates. By financial costs I mean registration fees, exam fees etc, which are especially high when you convert USD to local currencies)
On difficulty. The joint entrance exam certainly defeats SAT is you judge it on the basis of academic toughness, rigour, depth of thinking, competition etc. It also defeats all ther engineering examinations (AIEEE, BITS, Common Entrance Exams of various states) on the same metric. This can be ascertained by looking at the average scores or comparing the questions. However it will still fall short when you compare it (specific sections) to (specific) Olympiads, which require greater rigour and indepth thinking.I
ts just that the acceptance ratio is so so so so so so low that cracking JEE and trying to get the most wanted branch in the most wanted campus i.e. CSE @ iit bombay is almost impossible 😛
consider that JEE mains had 1.4M applications and last year AIR (All india rank) 75 was the last person to get CSE @IITB in GEN category so the acceptance rate is 75/1400000 = 0.000357 = 0.00005357%
there are total 880(including reserved category) students who got IITB in 2012 and number will not increase much this year either so the over all acceptance rate is 880/1400000 = 0.00062857142 = 0.062857142 %
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