How many hours will take if we start 3am from Delhi to Agra
Yes it will almost take 3 hours to reach agra but please consider extra half an hour in case of light traffic once you are in the city.
Saturdays and Sundays are busiest and rest is fine.
Maximum 3.5 hours
What I can assume that you would like to leave Delhi at 3 AM to visit Taj for sunrise, What is your hotel location in Delhi if it is Central Delhi, then cab driver should get you there in Agra in 3.5 hours via Yamuna Express way as there will not be any traffic in early hours, except heavy rainfall.