Quick Answer
There are about 29.57 grams in 1 fluid ounce. This conversion is useful for cooking, nutrition facts, and other areas where knowing the weight of a liquid volume is needed.
Explanation
A fluid ounce is a unit of volume used in the United States and some other countries. It is equal to about 29.57 milliliters.
A gram is a unit of mass in the metric system. There are 1000 grams in 1 kilogram.
To find out how many grams are in a fluid ounce, we need to know the density of water. Density measures how much mass is contained in a certain volume.
Water has a density of 1 gram per milliliter. This means that 1 milliliter of water weighs 1 gram.
Since there are 29.57 milliliters in 1 fluid ounce, and the density of water is 1 g/mL, there must be 29.57 grams in 1 fluid ounce.
This conversion applies to water and other liquids that have about the same density as water, like milk, juice, oil, etc. Substances that are more dense than water, like honey, will have more grams per fluid ounce. Less dense liquids like alcohol will have fewer grams per fluid ounce.
Uses for Converting Fluid Ounces to Grams
Some common uses for converting fluid ounces to grams include:
– Cooking recipes – Many recipes, especially baking recipes, will specify ingredient amounts by weight in grams as well as by volume in fluid ounces. Knowing that 1 fl oz ≈ 30 g allows you to use the units interchangeably.
– Nutrition info – Many nutrition labels provide serving size information in both fluid ounces and grams for liquid products like soups, juices, and milks. Knowing the weight of different volume measures allows you to compare products.
– Postage/shipping – Postal services and shipping companies may specify weight limits for different classes of mail or shipping in grams. Converting from fluid ounces to grams allows you to calculate if a liquid will meet the requirements.
– Laboratory work – Scientists often need to convert between mass and volume using density when working with liquids. Converting fluid ounces to grams allows them to calculate density, prepare solutions, and more.
– Conversions – Knowing how many grams are in a fluid ounce allows you to convert between US customary units and metric units for liquid amounts. This can be useful for following recipes from different countries, converting nutrition information, and other applications.
Conversion Formula
The conversion between fluid ounces and grams can be expressed in the following simple formula:
Grams = Fluid Ounces x 29.57
Or
G = fl oz x 29.57
Where:
– G = weight in grams
– fl oz = volume in fluid ounces
This formula relies on the density of water being approximately 1 g/mL.
Some examples calculating grams from fluid ounces:
– 1 fl oz = 29.57 g
– 2 fl oz = 59.14 g
– 0.5 fl oz = 14.79 g
The formula can also be reversed to convert grams to fluid ounces:
Fluid Ounces = Grams / 29.57
Examples calculating fluid ounces from grams:
– 29.57 g = 1 fl oz
– 118.28 g = 4 fl oz
– 44.36 g = 1.5 fl oz
So if you know the volume in fluid ounces or the weight in grams, you can easily convert between the two units.
Converting Other Units to Grams
The fluid ounce is a common US cooking measure, but you may also need to convert other units like cups, pints, quarts, liters, etc. Here are some handy conversions:
– 1 teaspoon (tsp) = 5 mL = 5 g
– 1 tablespoon (tbsp) = 15 mL = 15 g
– 1 cup (c) = 236.59 mL = 227 g
– 1 pint (pt) = 473.18 mL = 454 g
– 1 quart (qt) = 946.35 mL = 907 g
– 1 liter (L) = 1000 mL = 1000 g
So if a recipe calls for 2 cups of milk, you know that is approximately 454 g * 2 = 908 g.
Metric Conversions
The fluid ounce is not a commonly used unit in the metric system. But metric units like milliliters, liters, and grams are commonly used in science and in many countries.
It can be helpful to know some equivalencies between fluid ounces and metric units:
– 1 fl oz = 29.57 mL
– 1 mL = 0.03 fl oz
– 1 L = 33.81 fl oz
– 1 fl oz = 0.03 L
– 1 kg = 35.27 fl oz
– 1 fl oz = 0.03 kg
So if you have a 500 mL bottle of water, you know it is approximately 16.9 fl oz. And if you need 200 g of liquid for a recipe, then that is equivalent to about 6.8 fl oz.
Converting Fluid Ounces to Milliliters
The most direct conversion is between fluid ounces and milliliters. Since 1 fluid ounce is defined as 29.57 mL, converting between them is easy:
To convert fluid ounces to milliliters:
Milliliters = Fluid Ounces x 29.57
Examples:
– 1 fl oz = 29.57 mL
– 2 fl oz = 59.14 mL
– 0.5 fl oz = 14.79 mL
To convert milliliters to fluid ounces:
Fluid Ounces = Milliliters / 29.57
Examples:
– 29.57 mL = 1 fl oz
– 250 mL = 8.45 fl oz
– 100 mL = 3.38 fl oz
Converting Fluid Ounces to Liters
To convert fluid ounces to liters:
Liters = Fluid Ounces x 0.03
The 0.03 factor comes from the fact that 1 liter = 33.81 fluid ounces.
Examples:
– 1 fl oz = 0.03 L
– 8 fl oz = 0.24 L
– 20 fl oz = 0.59 L
To convert liters to fluid ounces:
Fluid Ounces = Liters / 0.03
Examples:
– 0.03 L = 1 fl oz
– 1 L = 33.81 fl oz
– 0.5 L = 16.91 fl oz
So a 2 liter soda bottle contains about 67.63 fluid ounces. And a gallon of milk at 3.79 liters is approximately 128 fluid ounces.
Fluid Ounces to Cups
Cups are another common cooking unit for liquids. To convert between fluid ounces and cups:
Cups = Fluid Ounces / 8
The conversion factor comes from the fact that 1 cup = 8 fluid ounces.
Examples:
– 8 fl oz = 1 cup
– 16 fl oz = 2 cups
– 24 fl oz = 3 cups
To go from cups back to fluid ounces:
Fluid Ounces = Cups x 8
For example:
– 1 cup = 8 fl oz
– 2 cups = 16 fl oz
– 1.5 cups = 12 fl oz
Fluid Ounces to Pints and Quarts
Pints and quarts are larger fluid volume units.
There are 16 fluid ounces in 1 pint.
There are 32 fluid ounces (4 cups) in 1 quart.
To convert fluid ounces to pints:
Pints = Fluid ounces / 16
Examples:
– 16 fl oz = 1 pint
– 32 fl oz = 2 pints
– 10 fl oz = 0.625 pints
To convert pints back to fluid ounces:
Fluid ounces = Pints x 16
For example:
– 1 pint = 16 fl oz
– 2 pints = 32 fl oz
– 0.5 pints = 8 fl oz
For quarts:
Quarts = Fluid ounces / 32
Examples:
– 32 fl oz = 1 quart
– 64 fl oz = 2 quarts
– 16 fl oz = 0.5 quarts
And fluid ounces to quarts:
Fluid ounces = Quarts x 32
– 1 quart = 32 fl oz
– 3 quarts = 96 fl oz
– 1.5 quarts = 48 fl oz
Converting Fluid Ounces to Gallons
There are 128 fluid ounces in 1 gallon.
To convert fluid ounces to gallons:
Gallons = Fluid ounces / 128
For example:
– 128 fl oz = 1 gallon
– 256 fl oz = 2 gallons
– 64 fl oz = 0.5 gallons
To convert gallons to fluid ounces:
Fluid ounces = Gallons x 128
– 1 gallon = 128 fl oz
– 5 gallons = 640 fl oz
– 2.5 gallons = 320 fl oz
Fluid Ounces to Teaspoons and Tablespoons
For smaller liquid amounts, it can be useful to convert fluid ounces to teaspoons and tablespoons.
There are 6 teaspoons (tsp) in 1 fluid ounce
There are 2 tablespoons (tbsp) in 1 fluid ounce
To convert fluid ounces to teaspoons:
Teaspoons = Fluid ounces x 6
Examples:
– 1 fl oz = 6 tsp
– 2 fl oz = 12 tsp
– 0.25 fl oz = 1.5 tsp
To convert teaspoons back to fluid ounces:
Fluid ounces = Teaspoons / 6
For example:
– 6 tsp = 1 fl oz
– 36 tsp = 6 fl oz
– 18 tsp = 3 fl oz
For tablespoons:
Tablespoons = Fluid ounces x 2
Examples:
– 1 fl oz = 2 tbsp
– 8 fl oz = 16 tbsp
– 0.5 fl oz = 1 tbsp
And to convert tablespoons back to fluid ounces:
Fluid ounces = Tablespoons / 2
– 2 tbsp = 1 fl oz
– 8 tbsp = 4 fl oz
– 3 tbsp = 1.5 fl oz
Approximate Fluid Ounces per Common Liquids
| Liquid | Fluid Ounces |
|---|---|
| 1 shot | 1 – 1.5 fl oz |
| Wine glass | 5 fl oz |
| Cup of milk | 8 fl oz |
| 1 can of soda | 12 fl oz |
| Mug of coffee | 12 – 16 fl oz |
| Pint of beer | 16 fl oz |
| Water bottle | 16 – 32 fl oz |
| Quart of milk | 32 fl oz |
| 2-liter soda bottle | 67.63 fl oz |
| Gallon milk jug | 128 fl oz |
This table gives estimates for the fluid ounce volumes of common liquid containers and servings.
Conclusion
There are approximately 29.57 grams in 1 fluid ounce. This conversion allows you to calculate the weight of a liquid volume in cases where both units are useful.
Some examples where converting between grams and fluid ounces is handy are cooking, nutrition information, shipping, science lab work, and converting between metric and imperial units.
The conversion can be expressed as a simple formula:
Grams = Fluid Ounces x 29.57
Or conversely:
Fluid Ounces = Grams / 29.57
Handy conversions between fluid ounces and other volume units like milliliters, cups, pints, quarts, gallons, teaspoons, and tablespoons are also useful for cooking and everyday estimations.
Knowing the number of grams in a fluid ounce allows fluid volumes and weights to be used interchangeably or converted when needed.
