Ounces to Grams
An instant ounces-to-grams converter, with the formula and a reference table below.
| Ounces | Grams |
|---|---|
| 1 oz | 28.349523 g |
| 2 oz | 56.699046 g |
| 3 oz | 85.048569 g |
| 5 oz | 141.747616 g |
| 10 oz | 283.495231 g |
| 25 oz | 708.738078 g |
| 50 oz | 1417.476156 g |
| 100 oz | 2834.952313 g |
How to use
- Enter a value in the Ounces field.
- The Grams figure appears immediately — no button to press.
- Typing in the Grams field converts back to Ounces the same way.
- Use the reference table for the values that come up most often.
Ounces to Grams formula
To convert ounces to grams, multiply by 28.3495231.
g = oz × 28.3495231
Why this factor: the ounce and the gram are both defined against the kilogram, so dividing one definition by the other gives 28.3495231 directly. Both definitions are set out in full below.
To go the other way, divide by 28.3495231 — or use the Grams to Ounces converter, which is the same calculation reversed.
Worked example
Given 2 oz, multiplying by 28.3495231 yields 56.699046 g.
2 oz × 28.3495231 = 56.699046 g
The converter above does this for any value you type, in either direction.
What is an ounce?
An ounce is one sixteenth of a pound, used for small weights in the US.
Definition: Exactly 28.349523125 grams — one sixteenth of the international avoirdupois pound.
Where it is used: Food packaging, postal weights, and coffee and spice quantities in the US.
Worth knowing: Not the same as a fluid ounce, which measures volume. Also distinct from the troy ounce (31.103 g) used for gold and silver.
What is a gram?
A gram is one thousandth of a kilogram, the everyday unit for food and small-object mass.
Definition: Exactly 0.001 kilogram by SI prefix definition.
Where it is used: Nutrition labels, recipes, postal rates, and laboratory weighing.
Ounces vs Grams
The ounce is an imperial unit while the gram is a metric unit. That is why the factor between them is not a round number: the two systems were defined independently and only later tied together by exact agreement.
Frequently asked questions
How many grams are in an ounce?
One ounce equals 28.3495231 grams.
What is the formula to convert ounces to grams?
Multiply the number of ounces by 28.3495231. To reverse it, divide by 28.3495231 instead.
How do I convert grams back to ounces?
Divide by 28.3495231, which is the same as multiplying by 0.0352739619.
How many grams are in 10 ounces?
10 oz works out to 283.495231 g.
Is there anything to watch out for with ounces?
Not the same as a fluid ounce, which measures volume. Also distinct from the troy ounce (31.103 g) used for gold and silver.
How is the ounce defined?
Exactly 28.349523125 grams — one sixteenth of the international avoirdupois pound.