Journal of Cosmology and Astroparticle Physics (JCAP) encompasses theoretical, observational and experimental areas as well as computation and simulation. The journal covers the latest developments in the theory of all fundamental interactions and their cosmological implications (e.g. M-theory and cosmology, brane cosmology). JCAP's coverage also includes topics such as formation, dynamics and clustering of galaxies, pre-galactic star formation, x-ray astronomy, radio astronomy, gravitational lensing, active galactic nuclei, intergalactic and interstellar matter.

JCAP's coverage includes all aspects of cosmology and particle astrophysics including:

Early Universe: inflationary cosmology, the origin of the cosmic asymmetry between matter and anti-matter, big-bang nucleosynthesis, cosmic microwave background.
Large-scale structure of the Universe.
Dark matter and dark energy: the nature of dark matter and its detection, vacuum energy and quintessence.
Neutrino physics and astronomy.
Gravitational waves.
Particle and nuclear astrophysics.
Black holes and their impact on cosmology.
Gamma ray astrophysics.
String theory and cosmology.