Cubic Inches to Metric Cups (in³ to cup)

1 cubic inch equals 0.065548256 metric cups exactly.

1 cubic inch = 0.065548256 metric cups

How to convert cubic inches to metric cups

To convert cubic inches to metric cups, multiply the number of cubic inches by 0.065548256. This factor is exact. To go the other way, multiply metric cups by 15.25593602 (rounded).

metric cups = cubic inches × 0.065548256

Example: 10 cubic inches = 0.65548256 metric 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 Inch (in³)

US & ImperialCurrent unit

Exactly 16.387064 mL. Used for engine displacement in the US and for small mechanical parts.

Cubic inch is a unit defined by a ruler. Take an inch, build a cube, and its volume is exactly 16.387064 milliliters under the modern definition of the inch as 25.4 millimeters. Its main role in history is as the building block behind other US volumes: the US gallon is defined as 231 cubic inches, so a cubic inch is exactly 1/231 of a gallon. Even the 42-gallon oil barrel works out to precisely 9,702 of them.

The cubic inch survives most visibly in American engines, which are abbreviated c.i.d. for cubic inch displacement, while the rest of the world and many modern automakers speak in liters. A 5.7 liter engine is about 350 cubic inches, a conversion made easy by the exact factor of 16.387064. Small mechanical parts are also sized in cubic inches in North America.

1 cubic inch = 0.016387064 liters (exactly).

Sources: Wikipedia: Cubic inch; NIST SP 811, Appendix B.8: conversion factors for volume

Metric Cup (cup)

Cooking & barCurrent unit

Exactly 250 mL. The cup used in Australia, New Zealand and most Commonwealth recipes.

A metric cup is a cup tamed by decimal thinking. Australia, Canada, New Zealand and some other former British colonies that metricated use a round 250 milliliters, exactly a quarter of a liter. Canada's older cup had been eight imperial fluid ounces, about 227.3 mL, so the metric version is noticeably larger, and Canadian recipes now usually use the 250 mL cup.

The metric cup is not an SI unit, only a practical convention, and it differs from the US cups in useful ways. It is about 6 percent larger than the US customary cup at 236.6 mL and about 4 percent larger than the 240 mL US label cup. Its arithmetic is simple: four cups make a liter, and a cup holds 50 metric teaspoons or 16 and two thirds tablespoons of 15 mL. Many recipes outside the US skip cups entirely and give dry ingredients in grams, because volume is a rough proxy for flour.

1 metric cup = 0.25 liters (exactly).

Sources: Wikipedia: Metric cup; Wikipedia: Cup (unit)

Related conversions

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