Ranu Pani or Ranupani is a volcanic lake in Ranu Pani Village, Senduro District, Lumajang Regency, East Java. Ranu Pani is part of the Bromo Tengger Semeru National Park (TNBTS). Initially, the area of Ranu Pani was around one hectare, but now it is estimated to be only 0.75 hectares due to the rapid sedimentation rate. The population of Ranu Pani is around 2,000 people.