The QCD equation of state

I present the recently published results by the HotQCD collaboration for the (2+1)-flavor QCD equation of state. The lattice calculation has been done on lattices with temporal extent Nt=6, 8, 10 and 12 using the Highly Improved Staggered Quark (HISQ) action. The data is extrapolated to the continuum limit in the temperature range 130-400 MeV. In that range we have calculated the trace anomaly, energy density, pressure as well as other thermodynamic observables. I also discuss how the thermodynamics of the low-temperature phase can be described by the Hadron Resonance Gas model, and how the high-temperature behavior compares with perturbative calculations.