A method for protecting a calculation on an elliptic curve, by an electronic circuit, wherein a point of an elliptic curve is multiplied by a digital quantity, comprising the steps of: initializing a first variable with a value which is a function of a random quantity; initializing at least a second variable with a value which is a function of the digital quantity; at least for a bit at 1 of the digital quantity, the first variable is updated by: a) subtracting a multiple of the random quantity; and b) adding the content of the second variable; and once all the bits of the digital quantity have been processed, subtracting from the first variable the product of the point by the random quantity to provide the result.