Math practice · reimagined
Primes
Turn Primes into a fight you actually want to win. Every problem is an attack — solve it faster than your opponent and you land the hit.
Ages 7–70 · no download · plays in your browser · 20 languages
How it works
Primes
Pick a fighter, choose Primes, and trust your numbers. The faster and cleaner you solve, the harder you hit — from gentle early grades all the way to Olympic-level challenges.
A prime number can only be built one way: 1 times itself. Nothing else divides into it evenly — it refuses to be split into equal groups.
Up here the numbers get bigger, so you test them. Try dividing by 2, then 3, then 5, 7, 11, 13… if any of them fits with nothing left over, the number is NOT prime. Watch out for sneaky ones like 91 — it looks prime, but 7 × 13 = 91, so it's hiding a factor.
Read whether the question wants the prime or the odd-one-out, then tap your pick.
More math to master
— Quick answers —
Primes: the short FAQ
- Is the Primes free to play?
- Yes. The Primes is free to start right in your browser — no download, no signup. Paid plans later unlock the full fighter roster and the deeper curriculum.
- Who is the Primes for?
- Anyone from 7 to 70. The early grades stay gentle for beginners, while the higher tiers will make even the confident sweat.
- Do I need to download anything to play the Primes?
- Nope. The Primes runs in any browser, and there's a mobile app on the same account if you'd rather train on your phone.
- Can the Primes be used in the classroom?
- Absolutely. Teachers run the Primes with a whole class and track who's improving — see the schools plan for per-student pricing and a teacher dashboard.