Skip to content
UnitCalculators.com

Grams to ounces

Multiply grams by 0.035274 to get ounces.

1 g = 0.035274 ozBIPM SI · NIST HB 44
g
5.2911oz

150 g = 5.2911 oz

How to convert grams to ounces

The ounce is one sixteenth of an avoirdupois pound, exactly 28.349523125 grams. The gram is one thousandth of a kilogram (10⁻³ kg) in the SI.

Worked example — 150 g: 150 × 0.035274 = 5.2911 oz.

Grams to ounces table

Common conversions. The reverse table is on ounces to grams.
GramsOunces
10 g0.35274 oz
25 g0.881849 oz
50 g1.7637 oz
100 g3.5274 oz
150 g5.2911 oz
200 g7.0548 oz
250 g8.8185 oz
500 g17.637 oz
1,000 g35.274 oz

Reverse and related

About grams and ounces

Gram (g)

1 g = 0.035274 oz

Definition. 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)

Ounce (oz)

1 oz = 28.3495 g

Definition. 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)

Where people use this

Grams: recipe and food weights, nutrition labels, postage. Ounces: recipe portions, letter mail, packaged food. A 250 g block of butter is about 8.8 oz.

How we know this is right
The factor is fixed by the standards that define the units, not chosen — so it is exact, not a measurement:
1 oz = 28.34952313 g, so 1 g = 1 ÷ 28.34952313 = 0.035274 oz.

Every value is carried to full double precision; the display is rounded.

Sources: NIST Handbook 44, Appendix C §5 (Tables of Equivalents); BIPM, The International System of Units (SI), 9th ed. (2019).

Questions people ask

How many ounces is 100 grams?

100 grams is about 3.53 ounces (100 × 0.035274). To convert grams to ounces, multiply by 0.035274 or divide by 28.35.

How many grams are in an ounce?

One avoirdupois ounce is exactly 28.3495 grams. Many recipes round it to 28 g.

Is 250 g the same as 8 oz?

Not quite: a 250 g block is about 8.8 oz, while 8 oz is 226.8 g. The half-pound and 250 g are close but not equal.

How many ounces is 500 grams?

500 grams is about 17.6 ounces, a little over one pound.

All gram conversions