A simple analytic formula for the probability of wave breaking at a given point is derived on the basis of Gaussian statistics. The result is found to depend on a nondimensionalized variance of the sea surface acceleration and a threshold parameter α. This parameter determines those values of the downward acceleration at the crest (values greater than αg, α positive) for which the wave is considered to be breaking. The results are related to other recent work on wave breaking and the choice of the parameter α is discussed.