Cubic Millimeters to US Cups (mm³ to cup)

1 cubic millimeter equals 0.000004226752838 US cups (rounded).

1 cubic millimeter = 0.000004226752838 US cups

How to convert cubic millimeters to US cups

To convert cubic millimeters to US cups, multiply the number of cubic millimeters by 0.000004226752838. The factor is rounded to 10 significant digits. To go the other way, multiply US cups by 236,588.2365.

US cups = cubic millimeters × 0.000004226752838

Example: 10 cubic millimeters = 0.00004226752838 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

Cubic Millimeter (mm³)

Metric (SI)Current unit

One thousandth of a milliliter. Used for tiny volumes.

Geometry supplies the name: a cubic millimeter is the volume of a cube whose edges are each one millimeter long, equal to 10 to the minus 9 cubic meters. Because 1,000 of them fill one cubic centimeter, it is one thousandth of a milliliter, and it is the smallest volume that is commonly written as a cube of length rather than with a liter prefix.

Its tidy equality with the microliter rests on a decision taken in 1964, when the 12th General Conference on Weights and Measures went back to the original definition of the liter as exactly one cubic decimeter. From 1901 until then the liter had been tied to the space taken by a kilogram of water, which made it about 1.000028 cubic decimeters, so volumes in cubic millimeters and microliters differed very slightly. Today 1 mm3 equals 1 microliter exactly, and the figure used here, 0.000001 liter, follows directly from that.

1 cubic millimeter = 0.000001 liters (exactly).

Sources: Wikipedia: Cubic metre; Wikipedia: Litre

US Cup (cup)

US customaryCurrent unit

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

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