Check Upcoming and Active Contests
Hi there! I made an online version of Coder Calendar. Site.
You will be able to see upcoming contests as well as active contests on sites like CodeChef, HackerRank, HackerEarth, Codeforces and TopCoder.
I made it keeping in mind that one might need to check schedule of contests on devices that don't have the required app/extension installed. The site looks good on mobile devices as well.
I hope it will be of use to you!
You can use the site like so: