Oz to Grams, oz to g Converter
Converting "8 oz of flour" from a recipe? Check whether the recipe means 8 oz of weight or 8 fluid oz of volume, they give completely different answers. Use weight mode for the first, ingredient mode for the second.
8 oz × 28.3495 = 226.8 g
One oz equals 28.3495 grams. To convert any weight in oz to grams, multiply by 28.3495: 8 oz = 226.8 g, 12 oz = 340.2 g, 16 oz (1 pound) = 453.59 g. That factor never changes and never depends on what you are weighing.
The catch is that recipes written in US customary units use the word "oz" for two different things. A weight oz measures mass and converts at 28.3495 g. A fluid oz measures volume and converts to grams only once you know what is filling the cup. This converter handles both: weight mode for straight oz to g, and ingredient mode for cups and fluid oz.
How many grams are in an oz?
There are 28.349523125 grams in one avoirdupois oz, the oz used on food packaging, postal scales and kitchen scales across the United States. The value is exact by definition, not a measurement: the international pound was fixed at 0.45359237 kg in 1959, and an oz is one sixteenth of that. For everyday work, 28.3495 g is more precision than any kitchen scale can resolve, and 28.35 g is fine for cooking.
Going the other way, one gram is 0.035274 oz. The anchors worth memorising: 4 oz = 113.4 g, 8 oz = 226.8 g, 16 oz = 453.59 g, and 1 lb = 16 oz = 453.592 g. A US stick of butter is 4 oz, which is why it weighs 113 g.
How to convert oz to g
Multiply oz by 28.3495. That is the whole method: grams = oz × 28.3495. To go back, divide grams by 28.3495. There is no second step, no correction factor and no ingredient adjustment, 3 oz of saffron and 3 oz of gravel both weigh 85.05 g. For a pounds-and-oz figure, convert the pounds first (× 453.592) and add the oz: 2 lb 6 oz = 907.18 + 170.10 = 1077.3 g.
The only thing that can go wrong is starting from the wrong number. If the figure describes a space rather than a heft, a cup, a fluid oz, a measuring line, multiplying by 28.3495 gives an answer that looks plausible and is wrong. Ingredient mode exists for that case.
- Decide whether your figure is a weight in oz or a volume in fluid oz or cups. If it came off a scale or a package label, it is weight.
- For weight, multiply the number of oz by 28.3495 to get grams. For volume, switch to ingredient mode and pick the ingredient so the tool can apply its density.
- Round to the precision your work needs, whole grams for cooking, one decimal for baking, two for anything measured on a jeweller's or lab scale.
What is an oz?
The oz (symbol: oz) is a unit of mass in the US customary and imperial systems, equal to 1/16 of a pound, or 28.349523125 g. Its full name is the avoirdupois oz, and it is the oz meant by every food label, kitchen scale and postal rate in the United States. When a package says "Net Wt. 10 oz", that is 283.5 g of product.
Two other oz exist and neither belongs in a kitchen. The troy oz (31.1035 g) survives only for precious metals, gold, silver, platinum, and is about 10% heavier; a "1 oz" gold coin holds 31.1 g, not 28.3 g. The fluid oz (29.5735 mL in the US) is not a mass at all: it measures volume, and only shares the name. No recipe, scale or shipping label means the troy oz.
What is a gram?
The gram (symbol: g) is the metric unit of mass equal to one thousandth of a kilogram. It was originally defined as the mass of one cubic centimetre of water at its densest point, which is why 1 mL of water still weighs almost exactly 1 g, true for water and for very little else.
Grams scale cleanly: 1000 g = 1 kg, 1 g = 1000 mg. This is why professional bakers work in grams. A recipe written as 250 g flour, 150 g sugar, 125 g butter can be halved or tripled in your head, and every cook who follows it puts the same mass in the bowl. Oz and cups do neither reliably.
Weight vs volume: why a cup of flour and a cup of honey are not the same
One oz is 28.3495 g for flour, for honey, for butter, for lead. Mass is mass. If you put 1 oz of any substance on a scale and switch the scale to grams, it reads 28.3 g. Many pages publish "oz to grams" tables that vary by ingredient; those tables answer a different question and mislabel it. Nothing about flour makes an oz of it weigh less than an oz of honey.
Volume is where ingredients start to matter, and matter enormously. A US cup is a fixed space, 236.6 mL, and what you fill it with determines the mass. One cup of all-purpose flour is about 120 g because flour is light and full of air. One cup of granulated sugar is 200 g, butter 227 g, honey 340 g, nearly three times the flour, because honey packs that same space with far more matter. Same cup, wildly different weights. Ingredient mode applies the density you select: water 236.6 g per cup, milk 244 g, bread flour 127 g, packed brown sugar 213 g, powdered sugar 120 g, vegetable oil 218 g, uncooked rice 185 g, rolled oats 90 g.
The two modes answer different questions. Weight mode asks "I have a mass in oz, what is it in grams?" and multiplies by 28.3495, ignoring the ingredient because the ingredient is irrelevant. Ingredient mode asks "I have a volume of a specific thing, what does it weigh?" and needs a density table, because without one the question has no answer. The trap is a recipe line like "8 oz flour": read as weight it is 226.8 g, read as 8 fluid oz (one cup) it is roughly 120 g. British and Australian recipes almost always mean weight. American recipes that print cup measures alongside "oz" usually mean volume. If a recipe lists both, trust the weight.
Oz to grams conversion table
All values use the exact factor 1 oz = 28.349523125 g and are rounded to two decimal places. These are weight conversions and apply to every ingredient equally.
| Oz (weight) | Grams |
|---|---|
| 0.5 | 14.17 |
| 1 | 28.35 |
| 3 | 85.05 |
| 3.5 | 99.22 |
| 4 | 113.4 |
| 6 | 170.1 |
| 8 | 226.8 |
| 12 | 340.2 |
| 16 | 453.6 |
1 oz = 28.3495 g
Popular oz to grams conversions
Frequently asked questions
It depends on which "oz" your source means. 8 oz of weight is 226.8 g, that is 8 × 28.3495. 8 fluid oz is a volume (one US cup, 236.6 mL), and if it is filled with water it weighs about 237 g, which is where the 240 g figure people half-remember comes from. Filled with flour, that same cup weighs about 120 g. If the number came from a scale or a package, it is 226.8 g.
No. One oz is 28.3495 g whatever you are weighing. An oz of flour, an oz of honey and an oz of steel are all 28.3495 g, because they are all one oz of mass. Ingredients only matter when you start from a volume, a cup or a fluid oz, and want a weight. That is what ingredient mode is for.
A troy oz is 31.1035 g and is used only for precious metals such as gold, silver and platinum. It is not what your recipe means, not what your kitchen scale weighs in, and not what a food label uses. Anywhere outside a bullion dealer, "oz" means the avoirdupois oz of 28.3495 g. The gap is about 10%, which is why a 1 oz gold coin weighs 31.1 g.
Because a cup of flour is a volume and 8 oz is a weight, and for flour they are far apart. One cup of all-purpose flour holds about 120 g of flour, while 8 oz of weight is 226.8 g, close to two cups. The cup measurement happens to equal 8 fluid oz, which is a measure of space, not of mass. For water the two coincide closely by accident; for flour they do not.
An oz measures mass (28.3495 g). A fluid oz measures volume (29.5735 mL in the US). They are separate units that share a word. You cannot convert between them without knowing what substance is involved, because you are asking how much a given amount of space weighs. Scales read oz; measuring jugs read fluid oz.
There are 16 oz in a pound, and one pound is 453.592 g. That makes half a pound 8 oz (226.8 g) and a quarter pound 4 oz (113.4 g), the origin of the quarter-pound burger's 113 g patty. A US stick of butter is also 4 oz, which is why butter wrappers print 113 g.
Neither, if you can weigh instead. Dry measuring cups are meant to be filled and levelled off; liquid cups are meant to be filled to a line and read at eye level. Both measure the same volume, a US cup is 236.6 mL in either, but they invite different errors, and scooping flour with a dry cup can pack in 20% more than spooning it in. Weighing removes the problem entirely.
For baking, yes. A digital scale reading to 1 g with a tare button and a 5 kg capacity costs very little and eliminates every conversion question on this page. Tare the bowl, add flour until it reads 250 g, done. If you work with yeast, salt or spices in small quantities, a second scale reading to 0.1 g is worth having; 1 g resolution is too coarse for 3 g of instant yeast.
Multiply by 28 and add a little. Oz × 28 gets you within 1.2%, 6 oz × 28 = 168 g against a true 170.1 g. For a closer estimate, multiply by 28 then add 1% of the result. Going the other way, divide grams by 28 for a slightly low answer in oz, or halve twice and subtract a bit: 100 g is about 3.5 oz.
Buy 113 g, since 4 oz of weight is 113.4 g. Chocolate is sold by weight everywhere, so this is a straight weight-to-weight conversion and the ingredient does not enter into it. Common bar sizes of 100 g or 125 g bracket the target; 100 g is about 3.5 oz and 125 g is about 4.4 oz.