The article introduces a web-based cosmology calculator that computes various distances and times as functions of redshift for user-defined cosmological parameters. The calculator is available at http://www.astro.ucla.edu/~wright/CosmoCalc.html and includes features such as the light travel time distance ($D_{ltt}$), comoving radial distance ($D_{now}$), angular size distance ($D_A$), and luminosity distance ($D_L$). The author provides detailed mathematical formulas for these distances and discusses the implementation of the calculator using JavaScript. The calculator also supports the equation of state parameter $w$ and $w'$, allowing for more advanced cosmological models. Additionally, a modified version of the calculator is available for converting light travel times into redshifts. The article highlights the importance of these calculations in cosmology and provides a practical tool for researchers and students.The article introduces a web-based cosmology calculator that computes various distances and times as functions of redshift for user-defined cosmological parameters. The calculator is available at http://www.astro.ucla.edu/~wright/CosmoCalc.html and includes features such as the light travel time distance ($D_{ltt}$), comoving radial distance ($D_{now}$), angular size distance ($D_A$), and luminosity distance ($D_L$). The author provides detailed mathematical formulas for these distances and discusses the implementation of the calculator using JavaScript. The calculator also supports the equation of state parameter $w$ and $w'$, allowing for more advanced cosmological models. Additionally, a modified version of the calculator is available for converting light travel times into redshifts. The article highlights the importance of these calculations in cosmology and provides a practical tool for researchers and students.