We evaluate the on shell form factors of the
electron for arbitrary momentum transfer and finite electron mass,
at two loops in QED,
by integrating the corresponding dispersion
relations, which involve the imaginary parts known since a long time.
The infrared divergences are parameterized in terms of a fictitious
small photon mass. The result is expressed in terms of Harmonic
Polylogarithms of maximum weight 4. The expansions for small and
large momentum transfer are also given
