Plainfield is located in north New Jersey. Plainfield is between the Union, Somerset county. Plainfield has 6.02 square miles of land area and 0.01 square miles of water area. As of 2010-2014, the total Plainfield population is 50,423, which has grown 5.42% since 2000. The population growth rate is about the same as the state average rate of 5.47% and is much lower than the national average rate of 11.61%. Plainfield median household income is $53,099 in 2010-2014 and has grown by 13.74% since 2000. The income growth rate is much lower than the state average rate of 30.67% and is much lower than the national average rate of 27.36%. Plainfield median house value is $246,500 in 2010-2014 and has grown by 79.27% since 2000. The house value growth rate is lower than the state average rate of 87.30% and is much higher than the national average rate of 46.91%. As a reference, the national Consumer Price Index (CPI) inflation rate for the same period is 26.63%. On average, the public school district that covers Plainfield is worse than the state average in quality. The Plainfield area code is 908.