Fermi question · Technology

About how many numeric digits can the largest standard QR Code Model 2 hold?

Make a fast, defensible estimate before you reveal the reference answer. Think in factors, not exact recall.

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What is your estimate?

numeric digits

Use a positive number. Commas and scientific notation are okay.

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Reference answer

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≈ 7.1 thousand numeric digits

Fermi estimates are judged by scale, so a reasonable approximation can still earn a strong score.

One way to estimate it

Estimate from the largest QR grid and allow for structure, error correction, and encoding overhead.

  1. Largest grid177 × 177 ≈ 31,000 modules
  2. Usable data sharewell below the full module count after overhead
  3. Estimateorder of 10⁴ numeric digits

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