To answer the question “Is 64 oz equal to 2 liters?”, we first need to understand the different units of measurement for volume. Ounces (oz) and liters (L) are both units that are used to measure the volume or capacity of liquids. However, they are from different measurement systems.

Ounces are a unit of measurement in the US customary system, while liters are part of the metric system. The key to comparing these two units is to understand their relationship through conversion factors. With the right conversion, we can definitively determine if 64 oz is equal to 2 liters.

### The US Customary System

The US customary system of measurement originated in the British imperial system and is still widely used in the United States today. Volume measurements in this system include:

- Ounces (oz)
- Cups
- Pints (pt)
- Quarts (qt)
- Gallons (gal)

Some key facts about US customary volume units:

- 1 cup = 8 fluid ounces
- 1 pint = 2 cups OR 16 fluid ounces
- 1 quart = 2 pints OR 4 cups OR 32 fluid ounces
- 1 gallon = 4 quarts OR 8 pints OR 16 cups OR 128 fluid ounces

So ounces, although the smallest volume unit here, are the base unit for all the other measurements in this system. All conversions go back to ounces.

### The Metric System

The metric system is the standard system of measurement used universally in science, medicine, and most countries globally. Some key facts about metric volume units:

- The base unit of volume is the liter (L)
- 1 liter = 1000 milliliters (mL)
- 1 liter is just slightly more than 1 US quart in volume

So the liter is the fundamental unit of volume in the metric system, just like the ounce in US customary units.

## Converting Between US and Metric Volume Units

Now that we’ve reviewed the main volume units in each system, how do we convert between ounces and liters?

To relate units across measurement systems, we need to use **conversion factors**. A conversion factor essentially creates a ratio that equates one unit to another.

For US customary and metric volume units, some key conversion factors are:

- 1 gallon = 3.785 liters
- 1 liter = 33.814 ounces
- 1 ounce = 29.574 milliliters

Using these conversion factors allow us to convert any volume measurement between ounces, liters, milliliters, etc.

Let’s break one down as an example:

*1 gallon = 3.785 liters*

To convert this to a ratio:

Or:

So if we want to convert 10 gallons to liters using this conversion factor:

Being able to setup and use these types of conversion ratios is the key to converting between ounces and liters.

## Comparing Ounces and Liters

Now we can directly compare ounces and liters using the conversion factors.

Let’s setup a ratio comparing ounces and liters:

Simplifying:

So based on this conversion:

- 1 fluid ounce = 29.574 mL
- 1 liter = 33.814 fluid ounces

This means we can now convert between ounces and liters very easily.

For example, to convert 50 ounces to liters:

Or to convert 3 liters to ounces:

### Key Equivalents

Here are some key equivalent volumes between ounces and liters:

Ounces | Liters |
---|---|

33.814 oz | 1 L |

67.628 oz | 2 L |

101.442 oz | 3 L |

135.256 oz | 4 L |

169.07 oz | 5 L |

So based on the conversions, we can see that 64 oz is approximately equal to 1.89 liters, not exactly 2 liters.

## Conclusion

In summary, while 64 oz and 2 liters are similar volumes, they are **not equal** due to the different units:

- 64 ounces is a US customary unit
- 2 liters is a metric unit

Using conversion factors between gallons, liters, and ounces, we find:

- 64 oz converts to approximately 1.89 liters
- 2 liters converts to approximately 67.628 oz

So 64 oz does not exactly equal 2 liters. The conversion shows a clear difference between the two volumes in different measurement systems. Understanding conversions between units is key to comparing US customary and metric system measurements.

### References

1. NIST Reference on Constants, Units, and Uncertainty. (2022). *The NIST Reference on Constants, Units, and Uncertainty*. National Institute of Standards and Technology. https://physics.nist.gov/cuu/Units/outside.html

2. Factaboutglass. (2022). *Approximate Metric Equivalents to Common Imperial (US) Units*. Fact About Glass. https://www.factaboutglass.com/metric-system-conversion-approximate.html

3. tempsfordirexit. (2020). *A Guide Comparing Metric and Imperial Units*. tempsfordirexit. https://tempsfordirexit.com/2020/05/13/a-guide-comparing-metric-and-imperial-units