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A calm bright dojo-like study with an abacus, stacked wooden cylinders and a balance scale, a teenager comparing a tiny seed and a large stone on the scale

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OrderDojo

Before you trust a number, run three cheap checks — and catch most nonsense in seconds.

🔮 Open the sanity-check console →

Three checks that catch most nonsense

You don’t need to redo an experiment to smell a bad number. Scientists and careful readers run three fast sanity checks first. Orders of magnitude: count the powers of ten — a "100× better" claim is a two-order leap, and in a mature field that’s a flag. Dimensional analysis: track the units length, time, and mass through a formula, and a slip gives itself away — compute kinetic energy with v instead of v² and the dimensions come out as momentum, not energy. Calibration: score the probability you assigned against what actually happened, and being 90% sure and wrong turns out to cost almost the maximum. OrderDojo lets you run all three, on the claims you meet.

  1. Orders of magnitude. How many powers of ten does the claim jump? The bigger the leap, the stronger the evidence it needs.
  2. Dimensions. Do the units of the formula match the units of what it’s supposed to compute?
  3. Calibration. Was your confidence honest — do your 90%s come true about 90% of the time?

Everything runs on your device with exact arithmetic — no library, no network.

The three checks

  • Order of magnitude — the power of ten a quantity sits at; the gap between two is just counting powers of ten.
  • Dimensional analysis — tracking length, time, and mass through a formula so a unit error is visible before any number.
  • The Brier score — (your probability − what happened)²; it punishes confident-and-wrong far more than being unsure.

A console for ages 15–18 — no cast art here by design. Distinct from FermiForge: OrderDojo checks claims, it doesn’t estimate them.

More ways in

More ways to play

Who is in the denominator? Why f/4 follows f/2.8 Fifty-two cards in order

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Chosen from what this app is about. What you open is remembered on this device only.