  We present a detailed numerical study of finite volume effects for masses and
decay constants of the octet of pseudoscalar mesons. For this analysis we use
chiral perturbation theory and asymptotic formulae a la Luscher and propose an
extension of the latter beyond the leading exponential term. We argue that such
a formula, which is exact at the one-loop level, gives the numerically dominant
part at two loops and beyond. Finally, we discuss the possibility to determine
low energy constants from the finite volume dependence of masses and decay
constants.
