To convert acre-feet per day to cubic feet per minute, multiply by 30.25. 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.
Irrigation and reservoir release rates in the western United States. The airflow rating for fans, HVAC and compressors in the US.
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. The tables underneath give both a plain step-by-step lookup and a list of real quantities expressed in cubic feet per minute, so you can sanity-check whether your answer is a plausible size.
The formula
acre-feet per day- The amount you are converting, in acre-feet per day
30.249999999- The exact number of cubic feet per minute in one acre-foot per day
cubic feet per minute- The converted result
How it works, step by step
- Enter the value in acre-feet per day.
- It is multiplied by 30.249999999, the exact factor between the two units.
- The answer is shown in cubic feet per minute, with the reverse conversion beneath it.
- Check the reference table if you want a figure of comparable size.
Worked examples
A shower head: 0.0112 ac ft/d in cubic feet per minute
At 0.0112 ac ft/d (a shower head), the same quantity in cubic feet per minute is 0.0112 × 30.25 = 0.3388 CFM. One acre-foot per day is 30.25 cubic feet per minute, so the numbers grow as expected.
A fire hydrant: 4.2 ac ft/d in cubic feet per minute
At 4.2 ac ft/d (a fire hydrant), the same quantity in cubic feet per minute is 4.2 × 30.25 = 127.05 CFM. One acre-foot per day is 30.25 cubic feet per minute, so the numbers grow as expected.
How to read your score
Frequently asked questions
How many cubic feet per minute are in one acre-foot per day?
Exactly 30.249999999. 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 acre-feet per day to cubic feet per minute?
cubic feet per minute = acre-feet per day × 30.249999999. Reversed, acre-feet per day = cubic feet per minute ÷ 30.249999999, which is the same as multiplying by 0.0330578512407.
Which is the bigger unit, the acre-foot per day or the cubic foot per minute?
The acre-foot per day. One acre-foot per day equals 30.25 cubic feet per minute.
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 acre-foot per day?
Irrigation and reservoir release rates in the western United States.
What is a cubic foot per minute?
The airflow rating for fans, HVAC and compressors 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 ac ft/d to CFM in my head?
Plenty of people do this in their head: multiply by 30 instead of using the exact factor 30.25. At 100 that shortcut gives 3000 cubic feet per minute, off by 25 cubic feet per minute or about 0.83%. Fine for a rough estimate, not fine for anything you are cutting to size or dosing.
Acre-Feet Per Day to cubic feet per minute reference tables
| Acre-Feet Per Day | Cubic Feet Per Minute |
|---|---|
| 0.5 ac ft/d | 15.125 CFM |
| 1 ac ft/d | 30.25 CFM |
| 2 ac ft/d | 60.5 CFM |
| 3 ac ft/d | 90.75 CFM |
| 5 ac ft/d | 151.25 CFM |
| 10 ac ft/d | 302.5 CFM |
| 20 ac ft/d | 605 CFM |
| 25 ac ft/d | 756.25 CFM |
| 50 ac ft/d | 1512.5 CFM |
| 75 ac ft/d | 2268.75 CFM |
| 100 ac ft/d | 3025 CFM |
| 250 ac ft/d | 7562.5 CFM |
| 500 ac ft/d | 15,125 CFM |
| 1000 ac ft/d | 30,250 CFM |
| 5000 ac ft/d | 151,250 CFM |
Exact factor: 1 acre-foot per day = 30.249999999 cubic feet per minute.
| Quantity | ac ft/d | CFM |
|---|---|---|
| A dripping tap | 7.005e-06 ac ft/d | 0.0002119 CFM |
| A bathroom tap | 0.007005 ac ft/d | 0.2119 CFM |
| A shower head | 0.01121 ac ft/d | 0.339 CFM |
| A garden hose | 0.02101 ac ft/d | 0.6357 CFM |
| A fire hydrant | 4.203 ac ft/d | 127.1 CFM |
| The Thames at London | 4553 ac ft/d | 1.377e+05 CFM |
Published reference values, converted with the same factor this page uses.