We present WFPC2 photometry of 21 stellar clusters of the Large Magellanic Cloud obtained on images retrieved from the Hubble Space Telescope archive. The derived colour magnitude diagrams (CMDs) are presented and discussed. This database provides a sample of CMDs representing, with reliable statistics, simple stellar populations with a large spread of age. The stars in the core of the clusters are all resolved and measured at least down to the completeness limit; the magnitudes of the main sequence terminations and of the red giant clump are also evaluated for each cluster, together with the radius at half maximum of the star density.