Starting with a reductive group G over a local field, one can define the spherical Hecke algebra as bi-invariant functions on the group with compact support. The Macdonald formula we are discussing here is the one giving the image, via the Satake isomorphism, of a characteristic function in the spherical Hecke algebra into the algebra of invariant polynomials under the Weyl group of G. The purpose of the talk is to discuss that Macdonald formula in the context of Kac-Moody groups over local fields.