We demonstrate a compact and lightweight platform to conduct automated semen analysis using a lensfree on-chip microscope. This holographic on-chip imaging platform weighs similar to 46 g, measures similar to 4.2 x 4.2 x 5.8 cm, and does not require any lenses, lasers or other bulky optical components to achieve phase and amplitude imaging of sperms over similar to 24 mm(2) field-of-view with an effective numerical aperture of similar to 0.2. Using this wide-field lensfree on-chip microscope, semen samples are imaged for similar to 10 s, capturing a total of similar to 20 holographic frames. Digital subtraction of these consecutive lensfree frames, followed by appropriate processing of the reconstructed images, enables automated quantification of the count, the speed and the dynamic trajectories of motile sperms, while summation of the same frames permits counting of immotile sperms. Such a compact and lightweight automated semen analysis platform running on a wide-field lensfree on-chip microscope could be especially important for fertility clinics, personal male fertility tests, as well as for field use in veterinary medicine such as in stud farming and animal breeding applications.