To convert US gallons per hour to imperial gallons per minute, multiply by 0.01387790308. 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.
Used for fuel burn and small pumps. The British pump unit, about 20% more volume per minute than the US gallon version.
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 imperial gallons per minute so the number you get has something to be compared against.
The formula
US gallons per hour- The amount you are converting, in US gallons per hour
0.0138779030779- The exact number of imperial gallons per minute in one US gallon per hour
imperial gallons per minute- The converted result
How it works, step by step
- Enter the value in US gallons per hour.
- It is multiplied by 0.0138779030779, the exact factor between the two units.
- The answer is shown in imperial gallons per minute, with the reverse conversion beneath it.
- Check the reference table if you want a figure of comparable size.
Worked examples
A dripping tap: 0.0951 GPH in imperial gallons per minute
Take a dripping tap, roughly 0.0951 GPH. The conversion is a single multiplication — 0.0951 × 0.0138779 — giving 0.00131979 gpm. Because the relationship is proportional, doubling the input doubles the answer to 0.00263958 gpm.
A garden hose: 285 GPH in imperial gallons per minute
Take a garden hose, roughly 285 GPH. The conversion is a single multiplication — 285 × 0.0138779 — giving 3.9552 gpm. Because the relationship is proportional, doubling the input doubles the answer to 7.9104 gpm.
How to read your score
Frequently asked questions
How many imperial gallons per minute are in one US gallon per hour?
Exactly 0.0138779030779. 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 hour to imperial gallons per minute?
imperial gallons per minute = US gallons per hour × 0.0138779030779. Reversed, US gallons per hour = imperial gallons per minute ÷ 0.0138779030779, which is the same as multiplying by 72.0569955264.
Which is the bigger unit, the US gallon per hour or the imperial gallon per minute?
The imperial gallon per minute. One US gallon per hour is only 0.0138779 of a imperial gallon per minute, so it takes 72.057 US gallons per hour to make one imperial gallon 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 US gallon per hour?
Used for fuel burn and small pumps.
What is a imperial gallon per minute?
The British pump unit, about 20% more volume per minute than the US gallon version.
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 GPH to gpm in my head?
Plenty of people do this in their head: divide by 70 instead of using the exact factor 0.01387790308. At 100 that shortcut gives 1.4285714 imperial gallons per minute, off by 0.04078 imperial gallons per minute or about 2.94%. Fine for a rough estimate, not fine for anything you are cutting to size or dosing.
Us Gallons Per Hour to imperial gallons per minute reference tables
| Us Gallons Per Hour | Imperial Gallons Per Minute |
|---|---|
| 0.5 GPH | 0.00693895 gpm |
| 1 GPH | 0.0138779 gpm |
| 2 GPH | 0.0277558 gpm |
| 3 GPH | 0.0416337 gpm |
| 5 GPH | 0.0693895 gpm |
| 10 GPH | 0.138779 gpm |
| 20 GPH | 0.277558 gpm |
| 25 GPH | 0.346948 gpm |
| 50 GPH | 0.693895 gpm |
| 75 GPH | 1.04084 gpm |
| 100 GPH | 1.38779 gpm |
| 250 GPH | 3.46948 gpm |
| 500 GPH | 6.93895 gpm |
| 1000 GPH | 13.8779 gpm |
| 5000 GPH | 69.3895 gpm |
Exact factor: 1 US gallon per hour = 0.0138779030779 imperial gallons per minute.
| Quantity | GPH | gpm |
|---|---|---|
| A dripping tap | 0.0951 GPH | 0.00132 gpm |
| A bathroom tap | 95.1 GPH | 1.32 gpm |
| A shower head | 152.2 GPH | 2.112 gpm |
| A garden hose | 285.3 GPH | 3.959 gpm |
| A fire hydrant | 5.706e+04 GPH | 791.9 gpm |
| The Thames at London | 6.182e+07 GPH | 8.579e+05 gpm |
Published reference values, converted with the same factor this page uses.