To convert US gallons per day to cubic feet per hour, multiply by 0.005570021999. That factor is the whole relationship: both units measure volumetric flow, so the conversion is a proportion with no offset and no substance-specific constant.
Gas appliance and small-flow rating in the US. The rating unit for reverse-osmosis membranes and water demand.
Standard versus actual volume. Gas flow in CFM depends on pressure and temperature, which is why compressor ratings say SCFM and specify the reference conditions. Converting the number is exact; comparing two ratings measured at different conditions is not. Below the calculator there is a step table for the values people look up most, and a second table putting real volumetric flow figures into cubic feet per hour so the number you get has something to be compared against.
The formula
US gallons per day- The amount you are converting, in US gallons per day
0.00557002199947- The exact number of cubic feet per hour in one US gallon per day
cubic feet per hour- The converted result
How it works, step by step
- Enter the value in US gallons per day.
- It is multiplied by 0.00557002199947, the exact factor between the two units.
- The answer is shown in cubic feet per hour, with the reverse conversion beneath it.
- Check the reference table if you want a figure of comparable size.
Worked examples
A garden hose: 6850 GPD in cubic feet per hour
Take a garden hose, roughly 6850 GPD. The conversion is a single multiplication — 6850 × 0.00557002 — giving 38.1547 CFH. Because the relationship is proportional, doubling the input doubles the answer to 76.3093 CFH.
A fire hydrant: 1.37e+06 GPD in cubic feet per hour
Take a fire hydrant, roughly 1.37e+06 GPD. The conversion is a single multiplication — 1.37e+06 × 0.00557002 — giving 7630.93 CFH. Because the relationship is proportional, doubling the input doubles the answer to 15,261.9 CFH.
How to read your score
Frequently asked questions
How many cubic feet per hour are in one US gallon per day?
Exactly 0.00557002199947. Every figure on this page is that one number multiplied by your input, so the only rounding is at the display step.
What is the formula to convert US gallons per day to cubic feet per hour?
cubic feet per hour = US gallons per day × 0.00557002199947. Reversed, US gallons per day = cubic feet per hour ÷ 0.00557002199947, which is the same as multiplying by 179.532504557.
Which is the bigger unit, the US gallon per day or the cubic foot per hour?
The cubic foot per hour. One US gallon per day is only 0.00557002 of a cubic foot per hour, so it takes 179.533 US gallons per day to make one cubic foot per hour.
What does this quantity actually measure?
Both units measure volumetric flow. That is why a single factor is enough: there is no temperature offset and no material property involved, unlike conversions that cross between different quantities.
What is a US gallon per day?
The rating unit for reverse-osmosis membranes and water demand.
What is a cubic foot per hour?
Gas appliance and small-flow rating in the US.
Why does my answer differ from another converter?
Almost always because the other tool rounded the factor before multiplying. This page keeps full double precision through the calculation and rounds only for display, and it prints the factor it used so you can see where any difference came from.
Is there a quick way to do GPD to CFH in my head?
Plenty of people do this in their head: divide by 180 instead of using the exact factor 0.005570021999. At 100 that shortcut gives 0.55555556 cubic feet per hour, off by 0.001447 cubic feet per hour or about 0.26%. Fine for a rough estimate, not fine for anything you are cutting to size or dosing.
Us Gallons Per Day to cubic feet per hour reference tables
| Us Gallons Per Day | Cubic Feet Per Hour |
|---|---|
| 0.5 GPD | 0.00278501 CFH |
| 1 GPD | 0.00557002 CFH |
| 2 GPD | 0.01114 CFH |
| 3 GPD | 0.0167101 CFH |
| 5 GPD | 0.0278501 CFH |
| 10 GPD | 0.0557002 CFH |
| 20 GPD | 0.1114 CFH |
| 25 GPD | 0.139251 CFH |
| 50 GPD | 0.278501 CFH |
| 75 GPD | 0.417752 CFH |
| 100 GPD | 0.557002 CFH |
| 250 GPD | 1.39251 CFH |
| 500 GPD | 2.78501 CFH |
| 1000 GPD | 5.57002 CFH |
| 5000 GPD | 27.8501 CFH |
Exact factor: 1 US gallon per day = 0.00557002199947 cubic feet per hour.
| Quantity | GPD | CFH |
|---|---|---|
| A dripping tap | 2.282 GPD | 0.01271 CFH |
| A bathroom tap | 2282 GPD | 12.71 CFH |
| A shower head | 3652 GPD | 20.34 CFH |
| A garden hose | 6847 GPD | 38.14 CFH |
| A fire hydrant | 1.369e+06 GPD | 7628 CFH |
| The Thames at London | 1.484e+09 GPD | 8.264e+06 CFH |
Published reference values, converted with the same factor this page uses.