The ounces to grams factor
One ounce equals 28.3495 grams, so to convert ounces to grams you multiply by 28.3495. For example, 8 oz × 28.3495 = 226.80 g. This is the avoirdupois ounce used for food and everyday weight. Need the reverse? Use the grams to ounces calculator.
The factor is exact by definition rather than measured: the international pound is defined as 0.45359237 kg and an ounce is one sixteenth of that, giving 28.349523125 g. Everyday use rounds to 28.35 g, and many recipes round again to 28 g, which costs about 1.2% and only shows up over large quantities.
Many people follow this up with the grams to cups calculator.
How to use this calculator
Enter a weight in ounces and the converter instantly shows the equivalent in grams, rounded to two decimals — handy for converting US recipes to metric. Just multiply ounces by 28.3495.
Watch out for the troy ounce used for gold and silver: it is a different unit at 31.1035 g, roughly 10% heavier. If you are weighing precious metal rather than food, the 28.3495 g factor will understate the true weight.
The lbs to kg calculator is the natural next step once you have this figure.
Ounces to grams reference table
Common conversions:
| Ounces | Grams |
|---|---|
| 1 oz | 28.35 g |
| 4 oz | 113.40 g |
| 8 oz | 226.80 g |
| 12 oz | 340.19 g |
| 16 oz | 453.59 g |
Kitchen anchors worth remembering: a US stick of butter is 4 oz (113.40 g), a standard can of beans is 15 oz (425.24 g), a pound of pasta is 16 oz (453.59 g), and a 2 lb bag is 32 oz (907.18 g).
The cups to grams calculator answers the question that usually follows this one.
Frequently asked questions
- How do I convert ounces to grams?
- Multiply the ounces by 28.3495. For example, 8 oz × 28.3495 = 226.80 g.
- How many grams are in 8 ounces?
- 8 ounces equals about 226.80 grams.
- How many grams are in a pound?
- A pound is 16 ounces, which is 16 × 28.3495 = 453.59 grams.
- Is this the avoirdupois ounce?
- Yes — it uses the standard avoirdupois ounce of 28.3495 g, not the troy ounce.
- Is a fluid ounce the same as an ounce?
- No — a fluid ounce measures volume while an ounce measures weight, so the two only line up roughly for water. One US fluid ounce of water weighs about 1.04 ounces, and for oil or flour the gap is far bigger, so never convert fl oz with 28.3495.