So what can Colossus-Web do? A few highlights: 1) Graphical interface: you can plot tons of cosmological functions and download the data to csv files. 2) Multiple cosmologies: you can compare as many pre-programmed cosmologies as you want, or create your own.

3) Advanced cosmological parameters: different dark energy models, relativistic species, etc. 4) Advanced calculations: correlation functions, peak height, etc. Power spectra can be calculated via fitting functions or using CAMB.