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Gram | |
---|---|

The mass of this pen cap is about 1 gram | |

Unit information | |

Unit system | SI derived unit |

Unit of | Mass |

Symbol | g |

Unit conversions | |

1 g in ... | ... is equal to ... |

SI base units | 10^{-3} kilograms |

CGS units | 1 gram |

U.S. customary | 0.0353 ounces |

This article is about the unit of mass. For other uses of "g" "gram" and "gramme", see Gram (disambiguation).

Gram | |
---|---|

The mass of this pen cap is about 1 gram | |

Unit information | |

Unit system | SI derived unit |

Unit of | Mass |

Symbol | g |

Unit conversions | |

1 g in ... | ... is equal to ... |

SI base units | 10^{-3} kilograms |

CGS units | 1 gram |

U.S. customary | 0.0353 ounces |

The **gram** (alternative British English spelling: **gramme**;^{[1]} SI unit symbol: **g**) (Greek/Latin root *grámma*) is a metric system unit of mass.

Originally defined as "the absolute weight of a volume of pure water equal to the cube of the hundredth part of a metre, and at the temperature of melting ice"^{[2]} (later 4 °C), a gram is now defined as one one-thousandth of the SI base unit, the kilogram, or 1×10^{−3} kg, which itself is defined as being equal to the mass of a physical prototype preserved by the International Bureau of Weights and Measures.

The International System of Units (SI) unit symbol for the gram is "g" following the numeric value with a space, as in "640 g". It is not "gr" (which is the symbol for grains)^{[3]}^{:C-19}, "gm" (easily mistaken for "mg", milligrams) or "Gm" (giga-metre).

It was the base unit of mass in the original French metric system and the later centimetre-gram-second (CGS) system of units. The word originates from Late Latin *gramma* – a small weight.

The gram is today the most widely used unit of measurement for non-liquid ingredients in cooking and grocery shopping worldwide.

Most standards and legal requirements for nutrition labels on food products require relative contents to be stated per 100 g of the product, such that the resulting figure can also be read as a percentage.

- 1 gram (g) = 15.4323583529 grains (gr)
- 1 grain (gr) = 0.06479891 grams (g)
- 1 avoirdupois ounce (oz) = 28.349523125 grams (g)
- 1 troy ounce (ozt) = 31.1034768 grams (g)
- 1 gram (g) = 5 carats (ct)
- 1 gram (g) = 8.98755179×10
^{13}joules (J) (by mass–energy equivalence)

- 1 gram is roughly equal to 1 small paper clip or pen cap.
- The Japanese 1 yen coin has a mass of one gram.
^{[4]}(lighter than the British penny (3.56 g), the United States cent (2.5 g) or the "Euro-cent" (2.30 g)).

**^**"Weights and Measures Act 1985 (c. 72)".*The UK Statute Law Database*. Office of Public Sector Information. Retrieved 2011-01-26. "§92."**^**Décret relatif aux poids et aux mesures, 1795**^**National Institute of Standards and Technology (October 2011). Butcher, Tina; Cook, Steve; Crown, Linda et al. eds. "Appendix C – General Tables of Units of Measurement" (PDF).*Specifications, Tolerances, and Other Technical Requirements for Weighing and Measuring Devices*. NIST Handbook.**44**(2012 ed.). Washington, D.C.: U.S. Department of Commerce, Technology Administration, National Institute of Standards and Technology. ISSN 0271-4027. OCLC 58927093. Retrieved 30 June 2012.**^**"Circulating Coin Designs". Japan Mint. Retrieved 7 March 2010.