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We present a new calculation of the $D\to\pi$ and $D \to K$ form factors fromQCD light-cone sum rules. The $\overline{MS}$ scheme for the $c$-quark mass isused and the input parameters are updated. The results are $f^+_{D\pi}(0)=0.67^{+0.10}_{-0.07}$, $f^+_{DK}(0)=0.75^{+0.11}_{-0.08}$ and$f^+_{D\pi}(0)/f^+_{DK}(0)=0.88 \pm 0.05$. Combining the calculated formfactors with the latest CLEO data, we obtain $|V_{cd}|=0.225\pm 0.005 \pm 0.003^{+0.016}_{-0.012}$ and $|V_{cd}|/|V_{cs}|= 0.236\pm 0.006\pm 0.003\pm 0.013$where the first and second errors are of experimental origin and the thirderror is due to the estimated uncertainties of our calculation. We alsoevaluate the form factors $f^-_{D\pi}$ and $f^-_{DK}$ and predict the slopeparameters at $q^2=0$. Furthermore, calculating the form factors from the sumrules at $q^2<0$, we fit them to various parameterizations. After analyticcontinuation, the shape of the $D\to \pi,K $ form factors in the wholesemileptonic region is reproduced, in a good agreement with experiment.

Semileptonic charm decays $D \to \pi l \nu_{\l}$ and $D \to K l \nu_l$ from QCD Light-Cone Sum Rules