Observed arrival · 2026-08-22
CAL X, the scientific calculator with a daily misconception
A free French-language suite of 118 scientific calculators and converters, usable without an account.
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Why it surfaced
CAL X pairs practical tools—from pH and battery life to matrices and exam grades—with unusually good explanations of where intuition goes wrong. Its daily “contresens” feature explains why a 100% slope is 45° and why averaging 60 km/h with 40 km/h gives 48, not 50.
A free French-language suite of 118 scientific calculators and converters, usable without an account.
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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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