Birnagar is a village in Murarai I tehsil in district of Birbhum, West Bengal, India. As per the data provided by Census of India in 2011, total population of Birnagar was 4,699 which includes 2,376 males and 2,323 females. Birnagar covers 376.02 ha area. Pincode of Birnagar is 731219.