Dear aspirant,

The total marks, difficulty level, pattern of the exam keep varying every year for JEE Advanced and hence, it's hard to predict what marks you'll need. If you aim for a rank of below 5k in JEE Advanced you'll get a decent category rank that'll be good enough for you to get CSE in the top IITs. Generally, if you score about 50 % of the total marks, you'll be able to fall into the top 5k category.

Hope this helps.