One standard ounce equals 28.3495 grams, usually rounded to 28.35 grams for everyday use.
So if you are cooking, weighing food, checking a product label, or making a quick conversion, this is the number to remember.
1 oz = 28.35 g
This conversion refers to the standard avoirdupois ounce used for most everyday measurements. If you are weighing gold, silver, or other precious metals, check the unit first because these are commonly measured in troy ounces.
Ounces to Grams Quick Conversion Chart
Use this chart when you need a common ounces-to-grams conversion without doing the calculation yourself.
| Ounces | Grams |
|---|---|
| 0.25 oz | 7.09 g |
| 0.5 oz | 14.17 g |
| 1 oz | 28.35 g |
| 2 oz | 56.70 g |
| 3 oz | 85.05 g |
| 4 oz | 113.40 g |
| 5 oz | 141.75 g |
| 8 oz | 226.80 g |
| 10 oz | 283.50 g |
| 12 oz | 340.19 g |
| 16 oz | 453.59 g |
| 20 oz | 566.99 g |
Rounding to two decimal places is practical for most everyday conversions. For measurements not included in the chart, use the formula below.
How to Convert Ounces to Grams
To convert ounces to grams, multiply the number of ounces by 28.3495.
Grams = ounces × 28.3495
For example, if you have 3 ounces
3 × 28.3495 = 85.0485 g
Rounded to two decimal places, 3 oz = 85.05 g.
For an irregular measurement such as 7.5 ounces
7.5 × 28.3495 = 212.62125 g
So 7.5 oz ≈ 212.62 g.
For custom values, you can use a calculator or ask an AI assistant such as Unfox AI to handle the conversion and explain the calculation.
How to Convert Grams to Ounces
The conversion also works in reverse.
To convert grams to ounces, divide the number of grams by 28.3495.
Ounces = grams ÷ 28.3495
For example
100 ÷ 28.3495 ≈ 3.53 oz
So 100 grams is approximately 3.53 ounces.
This reverse conversion is useful when a recipe, package, or product specification gives a measurement in grams but you normally work with ounces.
Is an Ounce 28 or 28.35 Grams?
You may see one ounce described as either 28 grams or 28.35 grams because the conversion can be rounded to different levels of precision.
The standard conversion is approximately 28.35 grams per ounce. The more precise value is 28.349523125 grams.
Using 28 grams is simply a rough shortcut for mental calculations. It should not be confused with the standard conversion value.
For most people asking how many grams are in an ounce, 28.35 grams is the practical answer.
Avoirdupois Ounce vs Troy Ounce
One important exception appears when measuring precious metals.
The standard ounce used for food and most everyday goods is called the avoirdupois ounce. Gold, silver, and other precious metals are commonly measured using the troy ounce.
| Type of Ounce | Grams | Common Uses |
|---|---|---|
| Avoirdupois ounce | 28.3495 g | Food, packages, everyday goods |
| Troy ounce | 31.1035 g | Gold, silver, precious metals |
Because these units represent different masses, you should not use a standard ounces-to-grams conversion when a weight is specifically given in troy ounces.
For example, 1 troy ounce of gold equals approximately 31.1035 grams.
Ounce vs Fluid Ounce
An ounce and a fluid ounce measure different things.
An ounce (oz) is used for mass or weight in everyday conversion contexts. A fluid ounce (fl oz) measures volume.
This means you cannot generally convert fluid ounces directly to grams using the standard 28.35 conversion.
For example, the same volume of water and cooking oil can have different masses because their densities are different.
If a recipe lists an ingredient in oz, check whether the measurement refers to weight. If it uses fl oz, you are dealing with volume instead.
Which Conversion Should You Use?
Once you know which type of ounce you are working with, choose the level of precision based on the task.
| Situation | Recommended Approach |
|---|---|
| Everyday weight conversion | Use 28.35 g per oz |
| Cooking and baking | Use 28.35 g per oz or a kitchen scale |
| Quick mental estimate | Use about 28 g per oz |
| More precise calculation | Use 28.349523125 g per oz |
| Gold and silver | Check whether the value is in troy ounces |
| Fluid ounces | Convert based on volume and substance density |
The difference here is not about which number is correct. It is about choosing a level of precision that fits what you are measuring.
Common Ounce to Gram Examples
For quick reference, here are several common conversions.
How Many Grams Are in Half an Ounce?
0.5 oz ≈ 14.17 g
How Many Grams Are in 2 Ounces?
2 oz ≈ 56.70 g
How Many Grams Are in 4 Ounces?
4 oz ≈ 113.40 g
How Many Grams Are in 8 Ounces?
8 oz ≈ 226.80 g
How Many Grams Are in 16 Ounces?
16 oz ≈ 453.59 g
Sixteen avoirdupois ounces also equal one pound.
FAQ
How many grams are in 1 ounce?
One standard ounce equals approximately 28.35 grams.
Is an ounce 28 or 32 grams?
One ounce equals approximately 28.35 grams. The value may be rounded to 28 grams for rough estimates, but 32 grams is not the standard conversion.
How many grams are in an ounce of gold?
Gold is commonly measured in troy ounces. 1 troy ounce ≈ 31.1035 grams.
Is 1 oz always 28.35 grams?
No. The 28.35-gram conversion applies to the standard avoirdupois ounce. A troy ounce uses a different conversion.
Are fluid ounces the same as ounces?
No. Ounces are used for mass or weight in everyday conversion contexts, while fluid ounces measure volume. Converting fluid ounces to grams depends on the substance.
Final Answer
For everyday conversions, remember 1 oz = 28.35 g.
Multiply ounces by 28.3495 to get grams, or divide grams by 28.3495 to get ounces. Check the measurement type first when working with precious metals or fluid ounces.
