Westfield is located in north New Jersey. Westfield is part of Union County. Westfield has 6.72 square miles of land area and 0.02 square miles of water area. As of 2010-2014, the total Westfield population is 30,647, which has grown 3.38% since 2000. The population growth rate is lower than the state average rate of 5.47% and is much lower than the national average rate of 11.61%. Westfield median household income is $138,165 in 2010-2014 and has grown by 40.43% since 2000. The income growth rate is higher than the state average rate of 30.67% and is higher than the national average rate of 27.36%. Westfield median house value is $653,900 in 2010-2014 and has grown by 88.99% since 2000. The house value growth rate is about the same as 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 Westfield is much better than the state average in quality. The Westfield area code is 908.