Rounding is a display choice and should not be confused with the precision of a measurement. Keep sufficient guard digits during intermediate steps, then round according to the relevant convention. Exact definitions can produce many decimals for a converted value, but an instrument reading may have far fewer meaningful digits.
Important note
The calculation is performed locally from the listed unit definitions. Display results are rounded for readability; high-precision and regulated work should use the governing standard and appropriate significant figures.
Related conversions: Length, Mass & weight, Temperature, Digital storage, Energy, Power.
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