US Cups to Congii (cup to congius)
1 US cup equals 0.0722406829 congii (rounded).
How to convert US cups to congii
To convert US cups to congii, multiply the number of US cups by 0.0722406829. The factor is rounded to 10 significant digits. To go the other way, multiply congii by 13.84261554 (rounded).
congii = US cups × 0.0722406829
Example: 10 US cups = 0.722406829 congii.
Pints, quarts, gallons and fluid ounces differ between the US and the UK. Units are labeled 'US' or 'imperial' to avoid confusion.
Approximate value. Standards for the congius varied by place and period, so this converter uses the most commonly cited value. Treat results as estimates, not exact figures.
About these units
US Cup (cup)
One sixteenth of a US gallon, 236.588 mL (8 US fluid ounces). The standard US recipe cup.
Cups began as household drinking vessels, not scientific units, which is why they remain the messiest measures in the kitchen. The US customary cup was defined by slicing up the gallon: half a pint, or eight US fluid ounces, about 236.6 milliliters. Unlike the larger units, nobody ever fixed it to a physical vessel, so it exists only as a fraction of the gallon.
The customary cup is not the only American cup. For nutrition labels, US regulation defines a cup as exactly 240 milliliters, a rounder figure that sits slightly above the customary size. Packaged foods therefore list a serving in the legal cup while a measuring cup from the hardware store follows the customary definition. The gap is 3.4 milliliters, which hardly matters for soup but can matter in baking. Cup measures also hide the weight of dry ingredients, since a cup of sifted flour and a cup of packed flour differ substantially, which is why much of the world prefers grams.
1 US cup = 0.2365882365 liters (exactly).
Sources: Wikipedia: Cup (unit); NIST SP 811, Appendix B.8: conversion factors for volume; 21 CFR 101.9: nutrition labeling household measures
Congius (congius)
Six sextarii, about 3.27 L. A Roman liquid measure a little under a US gallon.
Eight congii made up one amphora quadrantal, and each congius was defined as a cube measuring half a Roman foot on each side. Wikipedia's table gives it as 3.27 L, which is the figure used here. The cube definition links it directly to the length standard, so any doubt about the exact length of the pes carries straight into the volume.
Inside the liquid scale, the congius was divided into 6 sextarii, and further down into 72 cyathi. Larger vessels such as the culeus were counted in congii, with 160 of them to the culeus. Because it came to roughly 3.3 L, it sits near the modern US gallon of 3.785 L, though it is noticeably smaller. Surviving vessels never match each other exactly, and the sextarii they imply range between 500 and 580 mL, so a congius from archaeology could fall anywhere from about 3.0 to 3.5 L.
1 congius = 3.275 liters (approximately).
Sources: Wikipedia: Ancient Roman units of measurement
Related conversions
- Congii to US cups (reverse)
- US cups to liters
- US cups to milliliters
- US cups to US gallons
- US cups to US fluid ounces
- US cups to cubic meters
- US cups to cubic centimeters
- US cups to US quarts
- US cups to US pints
- US cups to US tablespoons
- US cups to US teaspoons
- US cups to metric cups
- US cups to metric tablespoons
- Liters to congii
- Milliliters to congii
- US gallons to congii
- US fluid ounces to congii
See all volume units.