Ounces to Grams conversion

Ounces to grams in the kitchen and beyond

The ounce here is the avoirdupois ounce, the unit of weight used in American recipes, postal rates and nutrition labels. It is one sixteenth of a pound and equals 28.3495 grams. Do not confuse it with the fluid ounce, which measures volume: a fluid ounce of water weighs about 1.04 ounces, but a fluid ounce of flour weighs far less.

The formula

Multiply ounces by 28.3495 to get grams. For most cooking a factor of 28 is accurate enough; for postage, precious metals or laboratory work use the full value. Example: 8 oz × 28.3495 = 226.8 g, which is why a "half-pound" block of butter is sold as 227 g in metric countries.

Handy values

• 1 oz = 28.35 g
• 2 oz = 56.7 g
• 4 oz = 113.4 g (a quarter pound)
• 8 oz = 226.8 g (half a pound)
• 12 oz = 340.2 g
• 16 oz = 453.6 g (one pound)

Recipes

American recipes give dry ingredients in ounces or cups, European recipes in grams. Ounces convert cleanly; cups do not, because a cup of flour and a cup of sugar weigh different amounts. If a recipe lists both cups and ounces, trust the ounces and convert them to grams with this page.

Shipping and nutrition

Postal services price letters and small parcels by the ounce, while the rest of the world uses grams. Nutrition labels in the US list serving sizes in ounces with the gram equivalent in brackets, so you can cross-check: a 1.5 oz serving should read as 43 g.

The troy ounce exception

Gold, silver and platinum are weighed in troy ounces, which are heavier: 31.1035 g. If you are converting the price or weight of bullion, this page's factor does not apply.

Worked examples

A 6 oz steak. 6 × 28.35 = 170 g — the typical single portion in metric recipes.

A 3.5 oz bag of chips. 3.5 × 28.35 = 99 g, which is why the metric equivalent is sold as a 100 g bag.

A 1.5 oz letter. 1.5 × 28.35 = 42.5 g. In metric postal systems the next band is usually 50 g, so it goes at the base rate.

Frequently asked questions

How many grams are in an ounce? 28.3495 g. For cooking, 28 g is close enough; for anything sold by weight use the full value.

Is 4 oz a quarter of a pound? Yes: 16 oz make a pound, so 4 oz is a quarter pound, 113.4 g — the "quarter pounder" of hamburger fame is named after its uncooked patty weight.

Are ounces on a nutrition label weight or volume? Weight, unless written "fl oz". A "serving size 1 oz (28 g)" line is a weight; a "8 fl oz (240 mL)" line is a volume.

Related conversions

Sixteen ounces make a pound, so for larger amounts the pounds to grams converter (× 453.6) is handier. For liquids measured in fluid ounces, use fluid ounces to milliliters instead.