US Fluid Drams to US Cups (fl dr to cup)
1 US fluid dram equals 0.015625 US cups exactly.
How to convert US fluid drams to US cups
To convert US fluid drams to US cups, multiply the number of US fluid drams by 0.015625. This factor is exact. To go the other way, multiply US cups by 64.
US cups = US fluid drams × 0.015625
Example: 10 US fluid drams = 0.15625 US 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 Fluid Dram (fl dr)
One eighth of a US fluid ounce (3.6967 mL). Used in old pharmacy measures.
Drachma, the Greek coin and weight, lies behind the dram. The Attic drachma weighed about 4.37 g and the Roman one about 3.41 g, and the apothecaries borrowed the name for both a weight and a liquid measure. The US fluid dram is one eighth of a US fluid ounce, 3.6966911953125 mL, and it divides into 60 minims. Its British imperial counterpart, spelled drachm in pharmacy usage from around 1900, is smaller at 3.5516 mL.
Doctors once used the dram as the size of a teaspoonful, and early nineteenth-century prescriptions assumed a teaspoon held 60 minims. By 1876 household teaspoons had grown to 80 to 85 minims, which made that shortcut unreliable for medicine. Pharmacy is now metric, but the fluid dram survives in the capacity of pill bottles and vials. In casual speech a dram of whisky is a small pour, about 25 mL in an English pub and 35 mL in Scotland, which is a different thing from the pharmacist's unit.
1 US fluid dram = 0.003696691195 liters (approximately).
Sources: Wikipedia: Fluid dram; Wikipedia: Minim (unit)
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
Related conversions
- US cups to US fluid drams (reverse)
- US fluid drams to liters
- US fluid drams to milliliters
- US fluid drams to US gallons
- US fluid drams to US fluid ounces
- Liters to US cups
- Milliliters to US cups
- US gallons to US cups
- US fluid ounces to US cups
- Cubic meters to US cups
- Cubic centimeters to US cups
- US quarts to US cups
- US pints to US cups
- US tablespoons to US cups
- US teaspoons to US cups
- Metric cups to US cups
- Metric tablespoons to US cups
See all volume units.