How many grams are in a ounce?

1 oz = 28.3495 g. To convert any amount, multiply by 28.3495.

How do you convert ounces to grams?

Multiply the number of ounces by 28.3495 to get grams. The formula is shown in the "How it's calculated" section above.

Where does the conversion factor come from?

It's a published international standard. Most are defined exactly by international agreement (e.g. 1 inch = 25.4 mm exactly, 1 lb = 0.45359237 kg exactly). Source citations are listed under the formula above.

Unit converter — Mass

Ounces to grams converter

Convert ounces (oz) to grams (g). Source-cited conversion factor, exact to the displayed precision.

Results are mathematically exact for the displayed precision. How we calculate.

How it's calculated

Convert ounces to grams— the formula

Ounces convert to grams by multiplying by the published conversion factor. The factor below is exact to the precision shown, sourced from the citation under the formula.

g = oz × 28.3495

oz = g × 0.035274

Mass: SI base unit (BIPM). Avoirdupois conversions: 1 lb = 0.45359237 kg (international agreement 1959); 1 oz = 1/16 lb; 1 stone = 14 lb.

Questions

Frequently asked questions

How many grams are in a ounce?
1 oz = 28.3495 g. To convert any amount, multiply by 28.3495.
How do you convert ounces to grams?
Multiply the number of ounces by 28.3495 to get grams. The formula is shown in the "How it's calculated" section above.
Where does the conversion factor come from?
It's a published international standard. Most are defined exactly by international agreement (e.g. 1 inch = 25.4 mm exactly, 1 lb = 0.45359237 kg exactly). Source citations are listed under the formula above.