Brilliant (website)

Brilliant.org is an American for-profit company and associated community that features 90+ guided courses in three categories: maths, computer science and science. It operates via a freemium business model. Brilliant was founded in 2012. At the Launch Festival in March 2013, CEO and co-founder Sue Khim presented the idea of Brilliant, attracting funding from venture capitalist Chamath Palihapitiya. In August 2013, TechCrunch reported that Brilliant.org had secured funding from Palihapitiya's Social+Capital Partnership, as well as from 500 Startups, Kapor Capital, Learn Capital, and Hyde Park Angels. The website boasted over 100,000 users at that time. By April 2019, it had achieved a valuation of $50 million.

Originally, Brilliant hosted a variety of individual puzzles and occasionally monthly challenges. At one point, the individual puzzles included their Problem of the Week, a selection of the 15 best puzzles for the week. By 2025, the focus of the site was on active learning in STEM fields, as opposed to rote learning, and it does not support learning certifications. Further, the platform does not support any individual mentorship, though "courses are curated by industry experts".

As of 2025, the monthly cost was US$24.99 or US$299.88 per annum.

Brilliant.org consists of a ranking system, which begins and ends each week at Sunday 8PM PT / 11PM ET. You are placed into a league with 29 other players. You can either rank up to the next league, stay in the same league, or be relegated to the previous league.

The leagues are: Hydrogen, Lithium, Carbon, Neon, Titanium, Xenon, Barium, Neodynium, Tungsten, Einsteinium.