US Gallons to US Legal Cups (gal to cup (legal))
1 US gallon equals 15.7725491 US legal cups exactly.
How to convert US gallons to US legal cups
To convert US gallons to US legal cups, multiply the number of US gallons by 15.7725491. This factor is exact. To go the other way, multiply US legal cups by 0.06340129257 (rounded).
US legal cups = US gallons × 15.7725491
Example: 10 US gallons = 157.725491 US legal cups.
Pints, quarts, gallons and fluid ounces differ between the US and the UK. Units are labeled 'US' or 'imperial' to avoid confusion.
About these units
US Gallon (gal)
Exactly 231 cubic inches or 3.785411784 liters (128 US fluid ounces). About 17% smaller than the imperial gallon.
The US gallon is a survivor of English wine trade. Around 1706, a statute in Queen Anne's reign fixed the wine gallon at exactly 231 cubic inches, settling confusion among the competing gallons for wine, ale and corn. British colonies in North America used that wine gallon, and in 1824 Britain replaced all its gallons with a new imperial one while the United States kept the old measure. It was adopted as the legal US standard in 1836 and is still defined as exactly 231 cubic inches, or 3.785411784 liters.
That makes the US gallon about 17 percent smaller than the imperial gallon, a difference that explains why American and British fuel-economy figures cannot be compared directly. Everyday uses are milk jugs, paint cans and gasoline pumps. One gallon divides evenly into four quarts, eight pints, sixteen cups and 128 fluid ounces. A gallon of water weighs a little over 8 pounds, an easy figure to remember when loading a car with water jugs.
1 US gallon = 3.785411784 liters (exactly).
Sources: Wikipedia: Gallon; NIST SP 811, Appendix B.8: conversion factors for volume
US Legal Cup (cup (legal))
Exactly 240 mL, the 'cup' defined by US food-labeling law.
Nutrition labels in the United States do not use the traditional cup. Federal law, tied to FDA labelling rules, defines the legal cup as exactly 240 mL, which is a round metric figure sitting close to the customary cup of 8 US fluid ounces (about 236.6 mL, as NIST lists it). The difference is about 1.4 percent, small enough to matter little for a serving size.
The metric cup of 250 mL, used in Australia, Canada, New Zealand and some other countries, is a separate, slightly larger measure, and the legal cup is about 0.96 of it. Older cups varied far more. The Japanese go was about 180 mL and was legally defined in 1891, the Russian stakan about 246 mL and the Dutch kopje about 150 mL. An 1894 British book described a cup as about 6 imperial fluid ounces. Without a stated standard, a recipe cup can therefore differ noticeably from country to country.
1 US legal cup = 0.24 liters (exactly).
Sources: Wikipedia: Cup (unit); NIST Guide to the SI, Appendix B.8: conversion factors
Related conversions
- US legal cups to US gallons (reverse)
- US gallons to liters
- US gallons to milliliters
- US gallons to US cups
- US gallons to US fluid ounces
- US gallons to cubic meters
- US gallons to cubic centimeters
- US gallons to US quarts
- US gallons to US pints
- US gallons to US tablespoons
- US gallons to US teaspoons
- US gallons to metric cups
- US gallons to metric tablespoons
- Liters to US legal cups
- Milliliters to US legal cups
- US cups to US legal cups
- US fluid ounces to US legal cups
See all volume units.