This page converts cubic feet per hour into acre-feet per day using the factor 0.0005509641873, and shows the reverse figure alongside it. Both units measure volumetric flow, which is why one number does the whole job.
Gas appliance and small-flow rating in the US. Irrigation and reservoir release rates in the western United States.
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. Two tables follow: rounded steps for quick lookup, and a set of real reference quantities converted into acre-feet per day, which is usually more useful than the bare number.
The formula
cubic feet per hour- The amount you are converting, in cubic feet per hour
0.000550964187346- The exact number of acre-feet per day in one cubic foot per hour
acre-feet per day- The converted result
How it works, step by step
- Enter the value in cubic feet per hour.
- It is multiplied by 0.000550964187346, the exact factor between the two units.
- The answer is shown in acre-feet per day, with the reverse conversion beneath it.
- Check the reference table if you want a figure of comparable size.
Worked examples
A shower head: 20.3 CFH in acre-feet per day
A shower head comes to about 20.3 CFH. Multiplying by the factor: 20.3 × 0.000550964 = 0.0111846 ac ft/d. Dividing the answer back by 0.000550964 returns the figure you started with, which is the quickest way to check you have the factor the right way up.
The Thames at London: 8.26e+06 CFH in acre-feet per day
At 8.26e+06 CFH (the thames at london), the same quantity in acre-feet per day is 8.26e+06 × 0.000550964 = 4550.96 ac ft/d. One cubic foot per hour is 0.000550964 acre-feet per day, so the numbers shrink as expected.
How to read your score
Frequently asked questions
How many acre-feet per day are in one cubic foot per hour?
Exactly 0.000550964187346. 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 cubic feet per hour to acre-feet per day?
acre-feet per day = cubic feet per hour × 0.000550964187346. Reversed, cubic feet per hour = acre-feet per day ÷ 0.000550964187346, which is the same as multiplying by 1814.99999994.
Which is the bigger unit, the cubic foot per hour or the acre-foot per day?
The acre-foot per day. One cubic foot per hour is only 0.000550964 of a acre-foot per day, so it takes 1815 cubic feet per hour to make one acre-foot per day.
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 cubic foot per hour?
Gas appliance and small-flow rating in the US.
What is a acre-foot per day?
Irrigation and reservoir release rates in the western United States.
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 CFH to ac ft/d in my head?
Plenty of people do this in their head: divide by 1800 instead of using the exact factor 0.0005509641873. At 100 that shortcut gives 0.055555556 acre-feet per day, off by 0.0004591 acre-feet per day or about 0.83%. Fine for a rough estimate, not fine for anything you are cutting to size or dosing.
Cubic Feet Per Hour to acre-feet per day reference tables
| Cubic Feet Per Hour | Acre-Feet Per Day |
|---|---|
| 0.5 CFH | 0.000275482 ac ft/d |
| 1 CFH | 0.000550964 ac ft/d |
| 2 CFH | 0.00110193 ac ft/d |
| 3 CFH | 0.00165289 ac ft/d |
| 5 CFH | 0.00275482 ac ft/d |
| 10 CFH | 0.00550964 ac ft/d |
| 20 CFH | 0.0110193 ac ft/d |
| 25 CFH | 0.0137741 ac ft/d |
| 50 CFH | 0.0275482 ac ft/d |
| 75 CFH | 0.0413223 ac ft/d |
| 100 CFH | 0.0550964 ac ft/d |
| 250 CFH | 0.137741 ac ft/d |
| 500 CFH | 0.275482 ac ft/d |
| 1000 CFH | 0.550964 ac ft/d |
| 5000 CFH | 2.75482 ac ft/d |
Exact factor: 1 cubic foot per hour = 0.000550964187346 acre-feet per day.
| Quantity | CFH | ac ft/d |
|---|---|---|
| A dripping tap | 0.01271 CFH | 7.005e-06 ac ft/d |
| A bathroom tap | 12.71 CFH | 0.007005 ac ft/d |
| A shower head | 20.34 CFH | 0.01121 ac ft/d |
| A garden hose | 38.14 CFH | 0.02101 ac ft/d |
| A fire hydrant | 7628 CFH | 4.203 ac ft/d |
| The Thames at London | 8.264e+06 CFH | 4553 ac ft/d |
Published reference values, converted with the same factor this page uses.