We investigate the crossover between weak localization and weak antilocalization in InAs nanowires of different diameters (75 nm-140 nm-217 nm). For a magnetic field applied perpendicularly to the nanowire axis, we extract the spin orbit and coherence lengths using a quasi-one-dimensional model of the conductance. We find a spin-orbit length inversely proportional to the width of the nanowire. When a parallel magnetic field is applied, we observe that the weak-antilocalization contribution is less affected by the magnetic field than in the perpendicular case.