Sender: KATHY G

How many grams are in 1 ounce?

Hi Kathy,

It depends!
1 ounce, avoirdupois = 28.350 grams (approx.) -- this is the ounce used commonly in the US. (There are 16 ounces in an avoirdupois pound.)

1 ounce, troy = 31.103 grams (approx.) -- this is used for precious stones and metals in the US; perhaps it is still used by druggists. (There are 12 ounces in a troy pound.)

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