Convert Cubic Inch to Imperial Gallon
Convert cubic inches to imperial gallons instantly. 1 cubic inch = 0.0036046501 imperial gallon — use the live calculator, the exact formula, a conversion table and worked examples. Also check the Imperial Gallon to Cubic Inch converter for the reverse conversion.
Units explained
Cubic Inch
A cubic inch is the volume of a cube one inch on a side (16.387 mL).
Derived by cubing the international inch (25.4 mm).
Used for engine displacement and small-part volumes.
1959 yard agreement.
Imperial Gallon
The imperial gallon is defined as exactly 4.54609 liters.
Set by the British Weights and Measures Act of 1824 as the volume of 10 lb of water.
Used for fuel and beverages in the UK and Commonwealth.
UK, 1824.
Cubic Inch to Imperial Gallon conversion formula
The relationship between cubic inches and imperial gallons:
To convert cubic inches to imperial gallons, multiply the value in cubic inches by 0.0036046501. To reverse, multiply imperial gallons by 277.4194327916.
How to use this converter
Type a value into the calculator. The result in imperial gallons updates as you type. Tap a quick value, copy the result with one click, or use the swap arrow to jump straight to the Imperial Gallon to Cubic Inch converter for the reverse direction.
Step-by-step: convert cubic inches to imperial gallons
- Write down the value in cubic inches (in³).
- Multiply that value by the factor 0.0036046501.
- The product is the equivalent value in imperial gallons (gal).
- To reverse, multiply the imperial gallon value by 277.4194327916.
Worked examples
Example 1 — Convert 1 in³ to gal:
1 × 0.0036046501 = 0.0036046501 gal
Example 2 — Convert 100 in³ to gal:
100 × 0.0036046501 = 0.360465015 gal
Real-world example — Packaging gauge
A 4-cubic inch plastic bag thickness is a common spec for grocery and freezer bags. Converting from cubic inches to imperial gallons is what packaging buyers do whenever they bridge US and metric supplier quotes.
4 in³ × 0.0036046501 = 0.0144186006 gal
Real-world example — Plastic film and laminate thickness
A 500-cubic inch sheet is a typical spec for ID-card laminates and film overlays. Converting to imperial gallons aligns the value with the unit most CAD systems and material datasheets prefer.
500 in³ × 0.0036046501 = 1.802325075 gal
Cubic Inch to Imperial Gallon conversion table
Standard reference values for converting cubic inches to imperial gallons:
| Cubic Inch [in³] | Imperial Gallon [gal] |
|---|---|
| 0.01 | 3.60465e-5 |
| 0.1 | 0.000360465 |
| 1 | 0.0036046501 |
| 2 | 0.0072093003 |
| 3 | 0.0108139504 |
| 4 | 0.0144186006 |
| 5 | 0.0180232507 |
| 10 | 0.0360465015 |
| 20 | 0.072093003 |
| 30 | 0.1081395045 |
| 40 | 0.144186006 |
| 50 | 0.1802325075 |
| 100 | 0.360465015 |
| 500 | 1.802325075 |
| 1000 | 3.6046501499 |
Frequently asked questions
How many imperial gallons is 1 cubic inch?
How do I convert cubic inches to imperial gallons?
How do I convert imperial gallons back to cubic inches?
How many imperial gallons is 100 cubic inches?
Popular volume unit conversions
Convert Cubic Inch to other volume units
Show all Cubic Inch conversions
Metric / SI (8 units)
US Customary (Liquid) (8 units)
Imperial (UK) (4 units)
Cubic (length-derived) (2 units)
Cooking / Culinary (3 units)
Sources & references
Conversion factor (1 in³ = 0.0036046501 gal) verified against the following authoritative sources:
- BIPM — The International System of Units (SI Brochure 9th ed.)
Official BIPM publication defining the seven SI base units (including the meter) and the rules for their use. The global authority on units of measurement.
- NIST — Guide to the SI
US National Institute of Standards and Technology reference covering the SI base and derived units with definitions and usage rules for US technical practice.
- NIST Special Publication 811 — Guide for the Use of the International System of Units
Detailed NIST guide covering exact conversion factors between SI and US customary units along with formatting and rounding conventions.
- NIST — Refinement of values for the yard and pound (Federal Register 1959)
The treaty (signed by US
- International Astronomical Union — System of Astronomical Constants
The IAU defines astronomical units including the AU (149597870700 m exactly) light-year and parsec used in astronomy and astrophysics.