Ounces to grams
Multiply ounces by 28.3495 to get grams.
4 oz = 113.3981 g
How to convert ounces to grams
The gram is one thousandth of a kilogram (10⁻³ kg) in the SI. The ounce is one sixteenth of an avoirdupois pound, exactly 28.349523125 grams.
Worked example — 4 oz: 4 × 28.3495 = 113.3981 g.
Ounces to grams table
| Ounces | Grams |
|---|---|
| 0.5 oz | 14.1748 g |
| 1 oz | 28.3495 g |
| 2 oz | 56.699 g |
| 3 oz | 85.0486 g |
| 4 oz | 113.3981 g |
| 6 oz | 170.0971 g |
| 8 oz | 226.7962 g |
| 12 oz | 340.1943 g |
| 16 oz | 453.5924 g |
Reverse and related
About ounces and grams
Ounce (oz)
1 oz = 28.3495 gDefinition. One sixteenth of an avoirdupois pound, exactly 28.349523125 grams
History and origin
The ounce comes from the Roman uncia, a twelfth of the libra; the modern avoirdupois ounce is instead one sixteenth of the pound. Through the 1959 agreement it works out to exactly 28.349523125 grams.
Current use
Ounces are used in the United States for food portions, packaged goods and letter mail, and worldwide for boxing weights and some recipes.
Source: NIST Handbook 44, Appendix C §5 (Tables of Equivalents)
Gram (g)
1 g = 0.035274 ozDefinition. One thousandth of a kilogram (10⁻³ kg) in the SI
History and origin
The gram was the original base of the metric system set out in 1795, defined as the mass of one cubic centimetre of water at the melting point of ice, before the larger kilogram was chosen as the SI base unit. It is now simply one thousandth of a kilogram.
Current use
Grams are the everyday metric unit for small masses: recipe ingredients, nutrition labels, medicine doses and postage.
Source: BIPM, The International System of Units (SI), 9th ed. (2019)
Where people use this
Ounces: recipe portions, letter mail, packaged food. Grams: recipe and food weights, nutrition labels, postage. A 16 oz (one pound) pack is 453.6 g.
Every value is carried to full double precision; the display is rounded.
Sources: BIPM, The International System of Units (SI), 9th ed. (2019); NIST Handbook 44, Appendix C §5 (Tables of Equivalents).
Questions people ask
How many grams is 1 ounce?
One ounce is 28.3495 grams. To convert ounces to grams, multiply by 28.3495, so 4 oz is about 113.4 g.
How many grams is 8 oz?
8 ounces is about 226.8 grams (8 × 28.3495), which is half a pound.
How many grams is 16 oz?
A 16 oz pack, which is one pound, is 453.6 grams.
Is an ounce 30 grams?
Roughly. The exact avoirdupois ounce is 28.35 g, so 30 g is a common rounded estimate used in cooking.