Precision measurements of alphas at HERA (H1 and ZEUS)

The precision measurements of the strong coupling, alphas, and its
energy-scale dependence performed at HERA by the H1 and ZEUS 
Collaborations are presented. A new HERA average value is also presented
using recent inclusive-jet cross-section measurements in 
neutral current deep inelastic scattering at high Q^2. The combined HERA
determinations of alphas at various energy scales clearly show 
the running of the coupling from these jet data alone and are in agreement
with the prediction of perturbative QCD.