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To begin your search, go to the alphabetical index below and click on the first letter of the word you are searching for.

capitalization: SI/metric units

When writing the names of SI/metric units in full, capitalize only the word Celsius.

Symbols for units

When using symbols, capitalize the 19 symbols based on personal names and the letter L for litre.

  • 20 A (amperes, named after André-Marie Ampère)
  • 273.16 K (kelvins, named after Lord Kelvin)
  • 4.5 T (teslas, named after Nikola Tesla)
  • 12 V (volts, named after Alessandro Volta)
  • 30 L (litres)

All the other symbols remain in lower case.

  • 2 m (metres)
  • 475 g (grams)

Symbols for prefixes

Capitalize the symbols for the prefixes from mega to yotta.

  • M (mega)
  • G (giga)
  • T (tera)
  • P (peta)
  • E (exa)
  • Z (zetta)
  • Y (yotta)

The symbols for the other prefixes remain in lower case. Consistency is important here because the letters m and p are both used in symbols for two different prefixes:

  • mg (milligram); Mg (megagram)
  • pm (picometre); Pm (petametre)