iCosmos › Compare

Compare cosmological models

Plot up to six universes on the same axes and read their values side by side. The first model follows the calculator's inputs; the others can be published models or your own parameters.

What you can compare

• Any of the calculator's curves against redshift, including the comoving, angular diameter and luminosity distances, comoving volume, age and the linear growth factor.
• Ratio plots, which show each model divided by the first, so differences of a few per cent are visible.
• Parameter sweeps: a family of models that differ in one parameter (for example w₀ from −1.2 to −0.8).
• A table of values at the chosen redshift, and PNG, PDF, SVG and CSV exports.

Built-in models

Classic concordance (Ω_m = 0.3, Ω_Λ = 0.7, H₀ = 70), Planck 2018, the DESI DR2 results for each published data combination, and teaching models: Einstein–de Sitter, open, closed, Milne, de Sitter and radiation-only universes. Sources are listed on the Reference page.

Open the iCosmos cosmology calculator

iCosmos 4.5.0 · updated 10 November 2026