CFS to GPM Converter
Convert cubic feet per second (CFS) to US gallons per minute (GPM). Multiply by 448.831. This is the conversion you need when sizing a pump or pipeline against a streamflow, water right or stormwater figure quoted in CFS.
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CFS to GPM conversion resultFree download
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How It Works
Streamflow records, water rights and drainage calculations are published in CFS, but pumps, valves and pipe schedules are specified in GPM. Converting turns a hydrology number into something you can take to a pump curve. One CFS is 448.831 GPM, so even small channel flows translate into large pumping duties.
CFS to GPM Formula
GPM = CFS × 448.831
One cubic feet per second equals 448.831 US gallons per minute. Going the other way, one US gallons per minute equals 0.00222801 cubic feet per second.
Worked Example
Converting 100 CFS:
100 × 448.831 = 44883.1 GPM
CFS to GPM Conversion Table
| CFS | GPM |
|---|---|
| 1 CFS | 448.831 GPM |
| 5 CFS | 2244.16 GPM |
| 10 CFS | 4488.31 GPM |
| 25 CFS | 11220.8 GPM |
| 50 CFS | 22441.6 GPM |
| 100 CFS | 44883.1 GPM |
| 250 CFS | 112208 GPM |
| 500 CFS | 224416 GPM |
| 1000 CFS | 448831 GPM |
Going the other way? Use the GPM to CFS converter. For any other unit pair, the full flow rate converter handles all ten supported units.
FAQ
Common questions about converting cubic feet per second to US gallons per minute.
Frequently Asked Questions
How do I convert CFS to GPM?
Multiply the CFS value by 448.831. For example, 5 CFS x 448.831 = 2244.16 GPM.
How many gallons per minute is 1 CFS?
One cubic foot per second equals 448.831 US gallons per minute, because one cubic foot holds 7.48052 US gallons and there are 60 seconds in a minute.
What is 2 CFS in GPM?
2 CFS equals 897.662 GPM. A common rule of thumb is that 1 CFS is "about 450 GPM", which is within 0.3% of the exact value.
How many gallons per day is 1 CFS?
One CFS equals 646,317 US gallons per day, or about 0.646 MGD. This is why municipal supply figures are often quoted in MGD rather than CFS.
Does CFS depend on the channel size?
No. CFS is already a volumetric flow rate, so converting it to GPM is a pure unit change. Channel geometry only matters if you are calculating the discharge in the first place — use the Manning equation calculator for that.
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