Planet-Brick is an online price comparison platform for LEGO and compatible construction-brick products. It helps builders find competitive prices, compare genuine discounts, and set price alerts, with account features for saving favorites and tracking them across devices. The site covers brands including LEGO, CaDA, Cobi, Pantasy, Lumibricks, JMBricklayer, BuildaMOC and others, and presents product offers with prices, delivery costs, discounts and set details.

Its catalog spans a wide range of interests, from cars, trains, aircraft and construction vehicles to architecture, city models, space, history, animals, plants, pop culture, films, games and fantasy. Visitors can browse themed collections, new releases, preorder items, popular models, and sets nearing retirement. Planet-Brick also lists MOC models, building instructions, individual bricks and parts, motors and other accessories. Related products include lighting kits, display cases, presentation frames, storage solutions, minifigure displays, printed elements and stickers. The website additionally offers a blog, tutorials, retailer searches, newsletter updates and information about site improvements, making it a discovery and shopping resource for construction-brick enthusiasts.