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We use a new compilation of the hadronic $R$-ratio from available data forthe process $e^+e^-\to$ hadrons below the charm mass to determine the strongcoupling $\alpha_s$, using finite-energy sum rules. Quoting our results at the$\tau$ mass to facilitate comparison to the results obtained from similaranalyses of hadronic $\tau$-decay data, we find $\alpha_s(m_\tau^2)=0.298\pm0.016\pm 0.006$ in fixed-order perturbation theory, and$\alpha_s(m_\tau^2)=0.304\pm 0.018\pm 0.006$ in contour-improved perturbationtheory, where the first error is statistical, and the second error combinesvarious systematic effects. These values are in good agreement with a recentdetermination from the OPAL and ALEPH data for hadronic $\tau$ decays. Webriefly compare the $R(s)$-based analysis with the $\tau$-based analysis.

The strong coupling from $e^+e^-\to$ hadrons