We investigate the rotational properties of strange quark stars using two representative quark matter (QM) equations of state (EOS): the vector MIT bag model and the density-dependent quark mass (DDQM) model. Through general-relativistic calculations of uniformly rotating sequences, we analyze their mass-radius relations, moments of inertia, quadrupole moments, surface redshifts, Keplerian frequencies, and energy components. A central result of this work is the full decomposition of the stellar energy budget in rotating strange stars, separating gravitational, internal, rotational, and binding energy contributions. Rotation amplifies the intrinsic EOS differences: the MIT model supports more massive ($M_{\max }\gtrsim 3.3M_{\odot }$) compact stars with larger moments of inertia and greater resistance to deformation, while the DDQM model produces larger radii, less massive stars limited by low Keplerian frequencies. Combined measurements of mass, radius, moment of inertia, surface redshift, and spin frequency can thus break the EOS degeneracy; massive, rapidly rotating pulsars favor MIT-like EOS, whereas larger moment of inertia in canonical stars point to a DDQM-like model. Moreover, by contrasting the rotational properties of quark stars with those of hadronic neutron stars, we identify distinctive multimessenger signatures of strange stars. These rotational observables, soon to be tightly constrained by Neutron Star Interior Composition Explorer and next-generation gravitational-wave detectors, offer a means to test the existence and composition of QM in compact stars.

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• Equations of state
• General relativity
• Quark matter
• Neutron stars & pulsars