American recipes, can labels and butcher counters give weights in ounces, while digital kitchen scales and most cookbooks from elsewhere work in grams. Converting is one multiplication — and once a recipe is in grams, scaling it up or down becomes simple arithmetic instead of juggling sixteenths of a pound.
How to use the ounces to grams converter
- Enter the weight in Ounces (oz). Fractions go in as decimals: ¼ oz = 0.25, ½ oz = 0.5.
- The answer appears in grams, rounded to two decimals, with kilograms and pounds underneath.
- The chart lists everything from a tenth of an ounce to 4 pounds (64 oz).
Ounces to grams formula
That factor is exact because the pound is defined as 453.59237 g and an ounce is one-sixteenth of a pound.
Worked example: a stick of butter
Step 1. A US stick of butter weighs 4 oz.
Step 2. 4 × 28.349523125 = 113.40 g.
Result. Weigh out 113 g on a metric scale; two sticks are 226.8 g.
Another one from the pantry: a 14.5 oz can of diced tomatoes holds 14.5 × 28.349523125 = 411.07 g. European cans are usually sold as 400 g, so they substitute almost one-for-one.
US kitchen staples in grams
| Item | Ounces | Grams |
|---|---|---|
| Half a stick of butter | 2 | 56.7 |
| Stick of butter | 4 | 113.4 |
| Typical meat or fish portion | 6 | 170.1 |
| Block of cream cheese | 8 | 226.8 |
| Bag of chocolate chips | 12 | 340.19 |
| Standard can of tomatoes | 14.5 | 411.07 |
| Can of beans | 15 | 425.24 |
| One pound of pasta or meat | 16 | 453.59 |
| Large can of tomatoes | 28 | 793.79 |
Professional bakers prefer grams because they are precise and add up cleanly. A recipe using 4 oz of butter, 8 oz of sugar and 10 oz of flour becomes 113 g, 227 g and 283.5 g; halving it means simply halving three numbers.
Weight ounces vs fluid ounces
Recipes from the US sometimes list liquids in “ounces” without saying which kind. If the ingredient is measured in a cup or jug, it is a fluid ounce (a volume), and you should convert it with the milliliters to fluid ounces converter or the cooking converter. If it is weighed on a scale, it is an ounce of mass, and this page is the right one. For water the two happen to be close — a fluid ounce of water weighs about 29.5 g — but for honey, oil or flour they are not.
Rounding for the kitchen
For most cooking, rounding to the nearest gram is fine; 28 g per ounce is close enough for amounts under about 4 oz. For baking powder, yeast, salt and anything measured in fractions of an ounce, keep one decimal place, since a small absolute error is a large percentage of a small amount. For postage and shipping, round up — carriers do. To go from grams back to ounces, use grams to ounces.
Frequently asked questions
How many grams are in an ounce?
Exactly 28.349523125 g. For cooking, 28.35 g is plenty precise, and 28 g is the figure most US nutrition labels print.
How many grams is 8 ounces?
8 oz is 226.8 g, half a pound. For butter that is two sticks, or one cup.
Is an ounce 28 grams or 30 grams?
A weight ounce is 28.35 g. The 30 figure belongs to the fluid ounce: US nutrition labels treat 1 fl oz as 30 mL, and a true US fluid ounce is 29.57 mL. The two units measure different things — mass and volume.
How do I convert ounces to grams for a recipe that says '1 cup'?
You can't do it with an ounce conversion, because a cup is a volume and its weight depends on the ingredient. A cup of flour is roughly 120–130 g, but a cup of sugar is about 200 g. Use an ingredient-aware cooking converter for cups.