Before you begin

• 24 puzzles, about 12 minutes

  One clock for the whole test. Spend it how you like.
• It starts easy

  Three easy ones to warm up, then it adjusts to you. A few will feel tricky. That's how it finds your level.
• You can go back one step

  Change your last answer if you need to. The next puzzle depends on it, so we'll pick a fresh one after.
• Somewhere quiet

  A quiet spot helps more than people expect.
• We time each puzzle

  We note how long each puzzle takes. If most answers come in faster than anyone could read them, we can't give you a fair result, so we'll tell you rather than guess. The timings also help us improve our puzzles.