GPM to mL/h Converter
Enter the flow rate in gpm below to convert it to ml/h.
Convert GPM (US) to mL/h
Enter a value in gpm (us) (GPM) to convert to ml/h (mL/h).
US Gallons per Minute to Milliliters per Hour Conversion Table
Table showing various us gallons per minute measurements converted to ml/h. Click any preset value or arrow to load it into the converter.
| GPM (US) (GPM) | mL/h (mL/h) |
|---|---|
| 0.0000001 GPM | 0.0227125 mL/h |
| 0.0000002 GPM | 0.0454249 mL/h |
| 0.0000003 GPM | 0.0681374 mL/h |
| 0.0000004 GPM | 0.0908499 mL/h |
| 0.0000005 GPM | 0.1135624 mL/h |
| 0.0000006 GPM | 0.1362748 mL/h |
| 0.0000007 GPM | 0.1589873 mL/h |
| 0.0000008 GPM | 0.1816998 mL/h |
| 0.0000009 GPM | 0.2044122 mL/h |
| 0.00000001 GPM | 0.0022712 mL/h |
How to Convert GPM to mL/h
To convert gpm to ml/h, multiply the flow rate by the following conversion ratio: 227,124.70704 ml/h/us gallons per minute.
Since one us gallons per minute is equal to 227,124.70704 ml/h, you can use this simple formula to convert:
The flow rate in ml/h is equal to the flow rate in gpm multiplied by 227,124.70704.
For example, here's how to convert 5 gpm to ml/h using the formula above.
How Many mL/h Are in a US Gallons per Minute?
There are 227,124.70704 ml/h in a us gallons per minute, which is why we use this value in the formula above.
Our us gallons per minute to milliliters per hour calculator automatically converts your flow rate measurements with full decimal and scientific precision across US customary, imperial, and SI metric standards.
GPM and ml/h are both units used to measure flow rate. Keep reading to learn more about each unit.
What Is a US Gallons per Minute?
A us gallons per minute is a unit of flow rate equal to 3.7854118 liters per minute (L/min), the base unit for flow rate. Standard US plumbing & pump flow rate (3.78541 L/min). [1]
The us gallons per minute is classified as a US customary unit of flow rate. GPM can be abbreviated as GPM; for example, 1 us gallons per minute can be written as 1 GPM.
When working with gpm (GPM) in formulas or technical specifications, always verify whether your target system uses SI metric, US customary, or British imperial standards.
In practice, gpm (GPM) are widely used across standard flow rate applications within US customary workflows, engineering documentation, and technical data sheets.
What Is a Milliliters per Hour?
A milliliters per hour is a unit of flow rate equal to 1/60,000 of a liters per minute (0.000016667 L/min). Medical IV infusion pump rate unit. [2]
The milliliters per hour is classified as a metric and SI-compatible unit of flow rate. mL/h can be abbreviated as mL/h; for example, 1 milliliters per hour can be written as 1 mL/h.
In the metric system, "milli" is the standard SI prefix for thousandths, or 10⁻³. This makes the milliliters per hour (mL/h) a convenient decimal multiple of the liters per minute (L/min).
In practice, ml/h (mL/h) are widely used across fine-tolerance laboratory, analytical, and micro-scale flow rate measurements within SI metric workflows, engineering documentation, and technical data sheets.
When converting flow rate between gpm (GPM) and ml/h (mL/h), keep full floating-point precision (1 GPM = 227,124.70704 mL/h; 1 mL/h = 0.000004403 GPM) during intermediate calculations and round only the final milliliters per hour figure to match your instrument tolerance.
More US Gallons per Minute & Milliliters per Hour Conversions
Need to calculate in the opposite direction? Use our ml/h to gpm (us) calculator to switch your starting unit immediately. You can also explore related tools such as converting ml/h to gpm (us), converting gpm (us) to liters per minute, or converting gpm (us) to m³/s.
Frequently Asked Questions
References
- [1]NIST SP 811 StandardNIST SP 811 (NIST SP 811 App. B.9 (Volume Divided by Time))·Flow Rate Metrology Standard — GPM (US) (GPM) to mL/h (mL/h)
- [2]NIST OWM SpecificationNIST OWM (SI Units — Volume & Flow Capacity)·Unit Specifications: US Gallons per Minute (GPM) (GPM) & Milliliters per Hour (mL/h)
- [3]BIPM ReferenceBIPM (Coherent Volumetric Flow Units (m³/s))·Conversion Factors & Mathematical Basis (GPM to mL/h)