  We have measured the absolute branching ratio of the K+ -> pi+ pi0 (gamma)
decay, using about 20 million tagged K+ mesons collected with the KLOE detector
at DAFNE, the Frascati phi-factory. Signal counts are obtained from the fit of
the distribution of the momentum of the charged decay particle in the kaon rest
frame. The result, inclusive of final-state radiation, is BR(K+ -> pi+ pi0
(gamma))=0.2065+/-0.0005_{stat}+/- 0.0008_{syst}.
