τ Challenge

How many digits of τ (tau) can you memorize? Tau (τ = 2π = 6.283185307...) is one of the most important constants in mathematics. Challenge yourself to memorize its decimal digits — and compete with players around the world. PRACTICE MODE Study tau's digits in bite-sized blocks of 50. Work through a progression of nodes, unlocking the next block as you master each one. Your progress is saved automatically so you can pick up where you left off. CHALLENGE MODE Type as many digits as you can from memory. One wrong digit and it's over. How far can you get? GLOBAL LEADERBOARD See how you rank against other players worldwide via Game Center. Track your all-time best and earn achievements at milestone digit counts. ACHIEVEMENTS Earn milestones as you progress — from your first 10 digits all the way to the legendary 1,000 digit mark. Whether you're a math enthusiast, a memory athlete, or just looking for a unique brain challenge — Tau is your game.