Convert CFS to GPM Calculator

Conversion Formula:

\[ Q_{gpm} = Q_{cfs} \times 448.83 \]

Flow Rate (GPM):

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1. What is CFS to GPM Conversion?

Definition: This calculator converts flow rate from cubic feet per second (CFS) to gallons per minute (GPM).

Purpose: It helps hydraulic engineers, plumbers, and water system designers work with different flow rate units.

2. How Does the Calculator Work?

The calculator uses the formula:

\[ Q_{gpm} = Q_{cfs} \times 448.83 \]

Where:

\( Q_{gpm} \) — Flow rate in gallons per minute
\( Q_{cfs} \) — Flow rate in cubic feet per second
448.83 — Conversion factor (1 ft³/s = 448.83 gpm)

Explanation: The conversion factor accounts for both volume (1 cubic foot = 7.48052 gallons) and time (1 second = 1/60 minute) conversions.

3. Importance of Flow Rate Conversion

Details: Many engineering specifications use CFS while equipment specifications often use GPM. Accurate conversion ensures proper system design and equipment selection.

4. Using the Calculator

Tips: Simply enter the flow rate in cubic feet per second (CFS). The value must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: Why is the conversion factor 448.83?
A: It combines the volume conversion (1 ft³ = 7.48052 gallons) with the time conversion (1 second = 1/60 minute): 7.48052 × 60 ≈ 448.83.

Q2: When would I need to convert CFS to GPM?
A: When working with pump specifications, pipe sizing charts, or irrigation systems that typically use GPM while your flow measurements are in CFS.

Q3: How accurate is this conversion?
A: The conversion is mathematically exact, though practical measurements may have instrumentation errors.

Q4: Can I convert GPM back to CFS?
A: Yes, divide GPM by 448.83 to get CFS. We can create a reverse calculator if needed.

Q5: What's a typical CFS value for residential water systems?
A: Residential systems typically range from 0.002 to 0.02 CFS (about 1-10 GPM).