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Card 366 of 9902026-09-17 issue

Observed arrival · 2026-09-17

Guesscale Turns Fermi Estimates Into a Daily Game

guesscale.com Observed source
Editorial interest 84/100 Selection signal · not a rating of the site

A three-question game that trains people to estimate difficult quantities and understand how far their intuition misses.

Landing page captured for the 2026-09-17 issue.

Field notes

The game asks players to estimate quantities that are difficult to know exactly, then compares each answer with a reference value using multiplicative distance. Its explanatory material emphasizes decomposing problems into assumptions and checking orders of magnitude rather than recalling trivia. The site includes worked examples about the Earth–Sun distance, internet use in 2025, and daily lightning flashes, plus unlimited practice and a browser-local Scale Profile that records directional error.

Observed signals

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Editorial observations of this landing page, not a rating.

OpenPublic substance visible
PrettyNotable craft visible
ProPolished or operationally mature
NicheUnusually specific use

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Landing page observed 2026-09-17. The live site may have changed.