We derive analytical expressions for the length, thickness, and curvature of an Airy light sheet in terms of basic parameters of the cubic phase and the paraxially defined focusing optics that form the beam. The length and thickness are defined analogously to the Rayleigh range and beam waist of a Gaussian beam, hence providing a direct and quantitative comparison between the two beam types. The analytical results are confirmed via numerical Fresnel propagation simulations and discussed within the context of light-sheet microscopy, providing a comprehensive guide for the design of the illumination unit.