Jan Mahamadpur is a village in Sarairanjan tehsil in district of Samastipur, Bihar, India. As per the data provided by Census of India in 2011, total population of Jan Mahamadpur was 2,187 which includes 1,087 males and 1,100 females. Jan Mahamadpur covers 41.8 ha area. Pincode of Jan Mahamadpur is 848505.