In this paper, the adoption of density-graded foams is evaluated for energy absorption purposes. The application field is protection from impact in sports and industrial environments, where suitable helmets are intended to reduce accelerations experienced by brain tissues, according to specific standards and injury criteria. The work consisted first of selecting foams of different densities and mechanical properties; then, the compressive stress–strain response was evaluated by means of tests conducted at different strain rates. A pneumatic machine was used to carry out quasi-static and intermediate strain rate tests, whereas dynamic tests were carried out at approximately 300 1/s by Split Hopkinson bar. Tests have been conducted first on uniform samples with different densities; in this way, constitutive models based on compressible hyperelasticity (hyperfoam) and plasticity (crushable foam) have been analyzed and calibrated. Then, compression tests on non-uniform samples with graded density have been conducted at different impact speeds for validation purposes. The mentioned constitutive models have been implemented in numerical simulations with Abaqus\explicit finite element software, where the experimental tests are replicated; the transmitted forces as well as the strain distributions obtained in the experiments and simulations have been quantitatively compared.