Planck time = 5.391 247 × 10−44 s

Value
5.391 247 × 10−44
Unit
s
Uncertainty
0.000 060 × 10⁻⁴⁴
Copy-ready
5.391247e-44

The Planck time, built from G, ℏ and c alone.

The scale at which quantum effects of gravity should matter — far beyond any experiment, and the reason G limits its precision.

NIST, Fundamental Physical Constants — Complete Listing (2022 CODATA adjustment), retrieved 2026-07-26.

Natural units and Planck units

Planck lengthPlanck massPlanck temperaturePlanck timeNatural unit of momentumNatural unit of time

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UsePhysics. "Planck time — 5.391 247 × 10−44 s." UsePhysics.com. https://usephysics.com/reference/planck-time. Value from the 2022 CODATA adjustment (NIST). Accessed [date].

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