how much percentage of 12th cbse is required for C.S ?

Since you have used the COMEDK UGET as tag, so first I shall answer the question with respect to COMEDK UGET

• General Candidates - 45% marks in Physics, Chemistry and Mathematics (PCM)
• SC/ST/OBC Candidates -  40% marks in PCM
• Should also have passed in the subjects (PCM) individually

So if you are a General Candidate, you must have 45% marks in PCM in Class 12 CBSE to be eligible to appear in COMEDK UGET. Then based on performance in the exam and merit, you can apply for Computer Science (CS) Course.

To get all details about COMEDK UGET, you may visit the website - https://engineering.careers360.com/articles/comedk-uget-eligibility-criteria

Also, you can pursue Computer Science (CS) Course via JEE Mains and JEE Advanced.

Previously, to be eligible for JEE Mains and JEE Advanced with respect to Class 12 marks, one had to secure 75% aggregate in Class 12 (or 65% for SC/ST). However, as per new changes, 75% aggregate mark is not compulsory. But the students need to pass Class 12 to be eligible for JEE Mains and JEE Advanced.

To get complete details about JEE Mains, you may visit the website - https://engineering.careers360.com/exams/jee-main

To get complete details about JEE Advanced, you may visit the website - https://engineering.careers360.com/exams/jee-advanced

Also, if you want to prepare for JEE Mains at affordable rates with quality features (like AI Learning, Personalized Timetables, Mock Tests, 24x7 Doubt Support, etc) , you may check out this link - https://learn.careers360.com/engineering/jee-main-preparation-material/