Understanding the Units: Cubic Inch Per Minute and Gallon Per Second

Both units belong to the volume flow rate family. A cubic inch per minute (in³/min) tells you how many cubic inches of fluid pass a point each minute. A gallon per second (gal/s) tells you how many US liquid gallons flow past the same point each second. The two units measure the same physical quantity, just on different scales.

Exact Conversion Factor

The relationship is fixed by two facts:

1. 1 US gallon = 231 cubic inches.
2. There are 60 seconds in a minute.

Combining them gives the exact factor:

1 in³/min = 0.00007212 gal/s

Conversion Formula

To move from cubic inches per minute to gallons per second, multiply by the factor above:

gal/s = (in³/min) × 0.00007212

Worked Example

Convert 250 in³/min to gal/s

1. Start with the source value: 250 in³/min.
2. Apply the formula: 250 × 0.00007212 = 0.01803 gal/s.
3. Result: 250 in³/min ≈ 0.0180 gal/s (rounded to four significant figures).

Practical Applications

• Engineers sizing fuel‑injection systems for small engines.
• Plumbers calculating water‑hammer relief rates in residential piping.
• HVAC technicians sizing refrigerant flow for compact chillers.
• DIY hobbyists converting pump specifications from imperial to US‑standard flow rates.

Cubic Inch Per Minute to Gallon Per Second Conversion Table

Each row applies the same rule: multiply the cubic inches per minute value by 0.00007212 to obtain gallons per second (rounded to four significant figures).

Key Takeaway

Switching between in³/min and gal/s is a simple multiplication by 0.00007212. Keep the factor handy, and you’ll instantly translate pump, engine, or plumbing data into the unit your project demands.

Ready to convert more flow rates? Explore our other unit‑conversion guides and keep your calculations flowing smoothly.