FREE
$0
Try the rhythm.
- 20 replayable sample questions
- All sample-bank friend races
- Answer explanations and timing
A LITTLE FRIENDLY COMPETITION.
Think you’re smarter
than your friends?
Find out in a three-minute problem-solving race. Then sharpen the skills that matter: SAT, coding interviews, calculus and more.
20 free questions · no card required · replay as often as you like
CHOOSE YOUR TRAINING GROUND
One skill at a time.
Original, template-generated exercises. Numerical variants build fluency; they are not millions of distinct lessons. For deeper reasoning, try the written-proof workshops below.
BUILD FROM THE ROOTS
Your skill tree.
Earn a fluency milestone with 3 different correct variants at the target pace. Prerequisites are a suggested path, not a barrier if you already know the material. Proof workshops require written reasoning and self-review; speed is not proof mastery.
SLOW DOWN TO GO DEEPER
Proof workshop.
From induction to real analysis and abstract algebra. State assumptions, justify every step, then compare your argument against a worked proof.
Need a starting point?
Worked proof
0.0s
The clueWatch for
Keys 1–4 to answer. Accuracy comes first; speed adds a bonus.
PRIVATE ROOMS · 2–8 PLAYERS
Your friends. The same ten questions.
3-minute race · same 20-question free bank for everyone · server-timed scores. Send your invite link to a friend and meet in the same room.
A little friendly pressure.
Correct answers earn 100 points minus one point per second, with a 10-point minimum. Incorrect answers earn zero. No cash prizes.
GO FROM CURIOUS TO CONSISTENT
A plan for your next level.
PRO
$12 / month
Build the reflex.
- All core generated practice
- SAT, calculus and number sense
- Coding, probability and ML foundations
- Fresh parameter variants on demand
MAX
$29 / month
Go deeper.
- Everything in Pro
- Advanced quant and systems patterns
- Engineering interview foundations
- Original company-style practice
Monthly recurring subscriptions when checkout is enabled. Cancel through Manage billing. Taxes, if applicable, are shown at checkout. Company-style exercises are original and not affiliated with or endorsed by Google or any employer.
Your progress, your account.
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