A web-based cosmology calculator is available at http://www.astro.ucla.edu/~wright/CosmoCalc.html, which computes times and distances as a function of redshift for user-defined cosmological parameters. The calculator uses equations derived from the Friedmann equations and includes various distance measures such as light travel time (D_ltt), angular size (D_A), luminosity (D_L), and proper radial distance (D_now). The calculator also allows for the specification of the equation of state parameter w and its derivative w'. It provides formulas for calculating these distances based on the cosmological parameters, including the Hubble constant, matter density, dark energy density, and other relevant parameters. The calculator also includes a version for converting light travel times into redshifts. The implementation uses JavaScript and numerical integration methods to evaluate integrals for the distances. The calculator also accounts for neutrino masses and the equation of state parameter w(z), allowing for more accurate cosmological calculations. The calculator is designed for interactive use and provides quick results for single cases. It can be used for various cosmological models, including open, flat, and closed CDM models, and has been tested with different parameters. The calculator is a valuable tool for researchers and students in cosmology to explore the universe's structure and evolution.A web-based cosmology calculator is available at http://www.astro.ucla.edu/~wright/CosmoCalc.html, which computes times and distances as a function of redshift for user-defined cosmological parameters. The calculator uses equations derived from the Friedmann equations and includes various distance measures such as light travel time (D_ltt), angular size (D_A), luminosity (D_L), and proper radial distance (D_now). The calculator also allows for the specification of the equation of state parameter w and its derivative w'. It provides formulas for calculating these distances based on the cosmological parameters, including the Hubble constant, matter density, dark energy density, and other relevant parameters. The calculator also includes a version for converting light travel times into redshifts. The implementation uses JavaScript and numerical integration methods to evaluate integrals for the distances. The calculator also accounts for neutrino masses and the equation of state parameter w(z), allowing for more accurate cosmological calculations. The calculator is designed for interactive use and provides quick results for single cases. It can be used for various cosmological models, including open, flat, and closed CDM models, and has been tested with different parameters. The calculator is a valuable tool for researchers and students in cosmology to explore the universe's structure and evolution.