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Cubic inch to Gallon Converter

Enter the value that you want to convert cubic inch (in³) to gallon (gal) or gallon to cubic inch.Also written as IN³ to GAL conversion.

1 cubic inch = 0.0043290 gallon

Formula: gallon = cubic inch value × 0.0043290

IN³ to GALcubic inch to gallon

in³
0.04329gal

10 cubic inch = 0.04329 gallon

Popular Volume Converters:

Cubic inch vs Gallon

Understanding the Cubic inch

Cubic inch (in³) is a unit of volume measurement. 1 cubic inch is equal to 0.0043290 gallon.

The Gallon Explained

Gallon (gal) is a unit of volume measurement. 1 gallon is equal to 231.0000000 cubic inch.

Volume Measurement Systems

Volume units are particularly confusing because the US and UK gallons differ (US gallon = 3.785 L, UK gallon = 4.546 L), as do their pints, cups, and fluid ounces. Cooking, fuel economy, beverage production, and pharmaceutical compounding all require precise volume conversions. Laboratory work uses milliliters and liters while US recipes specify cups, tablespoons, and fluid ounces.

cubic inch to gallon metric conversion table

0.01 in³=0.00004 gal
0.1 in³=0.00043 gal
1 in³=0.00433 gal
2 in³=0.00866 gal
3 in³=0.01299 gal
4 in³=0.01732 gal
5 in³=0.02165 gal
6 in³=0.02597 gal
7 in³=0.03030 gal
8 in³=0.03463 gal
9 in³=0.03896 gal
10 in³=0.04329 gal
11 in³=0.04762 gal
12 in³=0.05195 gal
13 in³=0.05628 gal
14 in³=0.06061 gal
15 in³=0.06494 gal
16 in³=0.06926 gal
17 in³=0.07359 gal
18 in³=0.07792 gal
19 in³=0.08225 gal
20 in³=0.08658 gal
30 in³=0.12987 gal
40 in³=0.17316 gal
50 in³=0.21645 gal
60 in³=0.25974 gal
70 in³=0.30303 gal
80 in³=0.34632 gal
90 in³=0.38961 gal
100 in³=0.43290 gal
200 in³=0.86580 gal
300 in³=1.29870 gal
400 in³=1.73160 gal
500 in³=2.16450 gal
600 in³=2.59740 gal
700 in³=3.03030 gal
800 in³=3.46320 gal
900 in³=3.89610 gal
1000 in³=4.32900 gal

How to Convert IN³ to GAL (Cubic inch to Gallon)?

We can convert cubic inch to gallon by using an example.

Example:

Convert 20 Cubic inch to Gallon?

We know 1 Cubic inch = 0.0043290 gallon; 1 Gallon = 231.0000000 cubic inch.

20 cubic inch = ___gal

20 × 0.0043290 = 0.08658 gal (we know 1 cubic inch = 0.0043290 gallon)

Answer:

20 cubic inch = 0.08658 gallon

Cubic Inches to US Gallons: Precision Volume Conversion

The US gallon is legally defined as exactly 231 cubic inches. This clean number comes from the historical definition of the wine gallon (a cylinder 7 inches in diameter and 6 inches tall: π × 3.5² × 6 ≈ 231 in³). To convert cubic inches to gallons, divide by 231. This conversion is commonly used in engine displacement, hydraulic cylinder sizing, and container manufacturing.

  1. Measure or obtain the volume in cubic inches.
  2. Divide by 231 to convert to US gallons.
  3. The result is the volume in US gallons.
  4. Example: 462 in³ ÷ 231 = 2 gallons.
💡 Tip: Engine displacement is expressed in cubic inches (especially classic cars). A 350 cubic inch engine = 350 ÷ 231 = 1.515 gallons — useful when calculating fluid capacities.

Cubic Inches to Gallons Reference

Common cubic inch volumes converted to gallons for automotive and industrial contexts:

Cubic inchGallon
1 in³0.004329 gal
57.75 in³0.25 gal
115.5 in³0.5 gal
231 in³1 gal
350 in³1.515 gal
462 in³2 gal
1,155 in³5 gal
2,310 in³10 gal

Solved Examples: Cubic Inches → Gallons

Question 1: A rectangular container is 11 in × 7 in × 6 in. How many gallons does it hold?

Solution:

Volume = 11 × 7 × 6 = 462 in³

Gallons = 462 ÷ 231

= 2 gallons

Answer: The container holds exactly 2 gallons.

Question 2: A hydraulic cylinder has an internal volume of 85 cubic inches. Express in gallons.

Solution:

Gallons = 85 ÷ 231

= 0.368 gallons

Answer: The cylinder holds 0.368 gallons (about 47 fluid ounces).

Question 3: A classic Chevy 454 engine — what is its displacement in gallons?

Solution:

Gallons = 454 ÷ 231

= 1.966 gallons

Answer: A 454 in³ engine displaces about 1.97 gallons (7.44 liters).

Practice Questions

Try solving these on your own to test your understanding:

  1. Convert 693 in³ to gallons. (Answer: 3 gallons)
  2. A tank is 20 in × 10 in × 12 in. How many gallons? (Answer: 10.39 gal)
  3. How many cubic inches is 4 gallons? (Answer: 924 in³)
  4. A 302 in³ Ford engine — gallons of displacement? (Answer: 1.307 gal)
  5. Convert 1,000 cubic inches to gallons. (Answer: 4.329 gal)

Why 231 Cubic Inches?

The US gallon's definition as 231 in³ traces back to the English wine gallon established in 1707 under Queen Anne. It was defined as a cylinder 7 inches in diameter and 6 inches deep (π × 3.5² × 6 = 230.91 ≈ 231). This specific number has remained the US standard ever since, while Britain moved to the imperial gallon (277.4 in³) in 1824. The 231 in³ definition makes conversions between cubic inches and gallons exact.

Engine Displacement: Cubic Inches vs. Liters

American muscle cars traditionally advertise engine size in cubic inches (302, 350, 396, 454, etc.), while modern cars and imports use liters. To convert: cubic inches ÷ 61.024 = liters. A 350 in³ = 5.7L, a 454 in³ = 7.4L. When calculating oil capacity or coolant volume for these engines, the cubic-inches-to-gallon conversion (÷231) helps determine how much fluid the block and components hold.

Key Takeaways

  • 1 US gallon = exactly 231 cubic inches (legal definition).
  • Divide cubic inches by 231 to get US gallons.
  • The 231 in³ definition dates back to the 1707 Queen Anne wine gallon.
  • Engine displacement in cubic inches ÷ 231 = gallons displaced.
  • For metric: cubic inches ÷ 61.024 = liters.

Cubic inch to Gallon Conversion Formula

gallon = cubic inch × 0.0043290

1 cubic inch = 0.0043290 gallon

1 gallon = 231.0000000 cubic inch

Reverse: cubic inch = gallon × 231.0000000

Frequently Asked Questions

How many gallon are in 1 cubic inch?

There are 0.0043290 gallon in 1 cubic inch. To convert cubic inch to gallon, multiply the value by 0.0043290.

How do I convert cubic inch to gallon?

Multiply your cubic inch value by 0.0043290 to get the equivalent in gallon. For example, 5 cubic inch = 5 × 0.0043290 = 0.02165 gallon.

How do I convert gallon to cubic inch?

Multiply your gallon value by 231.0000000 to get the equivalent in cubic inch. Alternatively, divide by 0.0043290.

What is 10 cubic inch in gallon?

10 cubic inch is equal to 0.04329 gallon.

What is 100 cubic inch in gallon?

100 cubic inch is equal to 0.43290 gallon.