# US Standard Volume

These are the most common measurements:

**Fluid Ounces****Cups****Pints****Quarts****Gallons**

**Fluid Ounces** (fl oz) are small**.**

About how much fits in a small medicine cup.

### Fluid Ounce!

"Fluid Ounce" is used for volume, "Ounce" is for mass, and they are different.

- For example: 1 fluid ounce of honey has a mass of about 1.5 ounces!
- But for water 1 fluid ounce has a mass of about 1 ounce.

If you mean an ounce of **fluid** say **"fluid ounce"** ("fl oz")

## Cups

A small glass holds about 8 fluid ounces, which is also called **1 cup**.

1 cup = 8 fluid ounces

We can measure volume using special Measuring Cups.

Here we have 2/3 cup (**two-thirds of a cup**) of milk, or about 5 fluid ounces

## Pints

A **pint** is equal to 2 cups (example: a large glass of milk!)

1 pint = 2 cups = 16 fluid ounces

## Quarts

When measuring many cups of liquid all put together we might want to use quarts.

A **quart** (qt) is the same thing as 4 cups or 2 pints.

1 quart = 2 pints = 4 cups = 32 fluid ounces

## Gallons

If we still need more liquid we can switch to using gallons.

A **gallon** (gal) is the same as 16 cups or 8 pints or 4 quarts. It is the largest liquid measurement.

(Note that a quart is a quarter of a gallon!)

1 gallon = 4 quarts = 8 pints = 16 cups

## In Summary:

1 gallon = 4 quarts = 8 pints = 16 cups = 128 fluid ounces

## Other Volume Measurements

### Cubic Inch

Volume is length by length by length,

so the Cubic Inch is a **cube that is 1 inch on each side**.

The Unit is written many ways, such as:

- in
^{3} - inch
^{3} - cu in
- cu inch
- cubic inches
- etc ...

### Barrel of Oil

1 oil barrel (bbl) is equal to 42 gallons (or about 160 Liters)

## More Examples

A fluid ounce is:

- very close to 30 milliliters (metric volume)
- more precisely 29.5735297 milliliters

A pint is:

- about half a liter
- more precisely 473.176473 milliliters

A quart is:

- about a liter
- more precisely 946.352946 milliliters

A gallon is:

- about 4 liters
- more precisely 3.7854118 liters