GPD to mL/h Converter
Enter the flow rate in gpd below to convert it to ml/h.
Convert GPD (US) to mL/h
Enter a value in gpd (us) (GPD) to convert to ml/h (mL/h).
US Gallons per Day to Milliliters per Hour Conversion Table
Table showing various us gallons per day measurements converted to ml/h. Click any preset value or arrow to load it into the converter.
| GPD (US) (GPD) | mL/h (mL/h) |
|---|---|
| 1 GPD | 157.725491 mL/h |
| 2 GPD | 315.450982 mL/h |
| 2.5 GPD | 394.3137275 mL/h |
| 5 GPD | 788.627455 mL/h |
| 10 GPD | 1,577.25491 mL/h |
| 15 GPD | 2,365.882365 mL/h |
| 20 GPD | 3,154.50982 mL/h |
| 25 GPD | 3,943.137275 mL/h |
| 30 GPD | 4,731.76473 mL/h |
| 50 GPD | 7,886.27455 mL/h |
How to Convert GPD to mL/h
To convert gpd to ml/h, multiply the flow rate by the following conversion ratio: 157.725491 ml/h/us gallons per day.
Since one us gallons per day is equal to 157.725491 ml/h, you can use this simple formula to convert:
The flow rate in ml/h is equal to the flow rate in gpd multiplied by 157.725491.
For example, here's how to convert 5 gpd to ml/h using the formula above.
How Many mL/h Are in a US Gallons per Day?
There are 157.725491 ml/h in a us gallons per day, which is why we use this value in the formula above.
Our us gallons per day 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.
GPD 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 Day?
A us gallons per day is a unit of flow rate equal to 0.0026288 liters per minute (L/min), the base unit for flow rate. Water treatment flow unit. [1]
The us gallons per day is classified as a US customary unit of flow rate. GPD can be abbreviated as GPD; for example, 1 us gallons per day can be written as 1 GPD.
When working with gpd (GPD) in formulas or technical specifications, always verify whether your target system uses SI metric, US customary, or British imperial standards.
In practice, gpd (GPD) are widely used across fine-tolerance laboratory, analytical, and micro-scale flow rate measurements 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 gpd (GPD) and ml/h (mL/h), keep full floating-point precision (1 GPD = 157.725491 mL/h; 1 mL/h = 0.0063401 GPD) during intermediate calculations and round only the final milliliters per hour figure to match your instrument tolerance.
More US Gallons per Day & Milliliters per Hour Conversions
Need to calculate in the opposite direction? Use our ml/h to gpd (us) calculator to switch your starting unit immediately. You can also explore related tools such as converting ml/h to gpd (us), converting liters per minute to gpm (us), or converting gpm (us) to liters per minute.
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 — GPD (US) (GPD) to mL/h (mL/h)
- [2]NIST OWM SpecificationNIST OWM (SI Units — Volume & Flow Capacity)·Unit Specifications: US Gallons per Day (GPD) (GPD) & Milliliters per Hour (mL/h)
- [3]BIPM ReferenceBIPM (Coherent Volumetric Flow Units (m³/s))·Conversion Factors & Mathematical Basis (GPD to mL/h)