Steam Charts is described as 'Measuring the trends of games on Steam can give some great insights, and this website aims to be a valuable tool to do so. An unpopular game does not necessarily indicate a bad game, and vice versa'. There are five alternatives to Steam Charts, not only websites but also apps for . The best alternative is Steam Database, which is both free and Open Source. Other great sites and apps similar to Steam Charts are Steam Spy (Freemium), VG Insights (Freemium), hypetraq (Free) and GitHyp (Free).
Steam Spy is Steam stats service based on Web API provided by Valve and cool idea of Kyle Orland from Ars Technica. Steam Spy automatically gathers data from Steam user profiles, analyzes it and presents in simple, yet beautiful, manner.