GPH to LPH Converter (Gallons per Hour ⇄ Liters per Hour)
Convert flow rate between gallons per hour (GPH) and liters per hour (LPH). Supports US and UK (imperial) gallons, with instant bidirectional conversion and clear formulas.
Flow Rate Converter
Using US gallons: LPH = GPH × 3.785411784
Tip: For quick estimates with US gallons, you can use 3.79 instead of 3.785411784.
Quick GPH to LPH reference table
| GPH (US) | LPH (approx.) | GPH (UK) | LPH (approx.) |
|---|---|---|---|
| 10 | 37.85 | 10 | 45.46 |
| 50 | 189.27 | 50 | 227.30 |
| 100 | 378.54 | 100 | 454.61 |
| 250 | 946.35 | 250 | 1,136.52 |
| 500 | 1,893.71 | 500 | 2,273.05 |
| 1000 | 3,785.41 | 1000 | 4,546.09 |
How to convert GPH to LPH
Gallons per hour (GPH) and liters per hour (LPH) are both measures of volumetric flow rate – how much liquid passes a point in one hour. To convert between them you only need the gallon-to-liter conversion factor.
US gallons to liters per hour
1 US gallon = 3.785411784 liters
LPH = GPH × 3.785411784
UK (imperial) gallons to liters per hour
1 UK gallon = 4.54609 liters
LPH = GPH × 4.54609
Step‑by‑step example (US gallons)
Problem: Convert 250 GPH (US) to LPH.
- Write the formula: LPH = GPH × 3.785411784
- Substitute the value: LPH = 250 × 3.785411784
- Calculate: LPH ≈ 946.35
Answer: 250 GPH ≈ 946.35 LPH.
How to convert LPH to GPH
To go the other way, divide by the same factor:
US gallons
GPH = LPH ÷ 3.785411784
UK gallons
GPH = LPH ÷ 4.54609
Where is GPH ↔ LPH used?
- Aquariums & fish tanks: pump and filter flow ratings.
- Irrigation & gardening: drip emitters and small pumps.
- Fuel systems: fuel pumps, generators, small engines.
- HVAC & cooling: coolant circulation, chiller flow.
FAQ
How do you convert GPH to LPH?
Multiply the GPH value by the gallon‑to‑liter factor. For US gallons use LPH = GPH × 3.785411784. For UK gallons use LPH = GPH × 4.54609.
How do you convert LPH to GPH?
Divide the LPH value by the gallon‑to‑liter factor. For US gallons use GPH = LPH ÷ 3.785411784. For UK gallons use GPH = LPH ÷ 4.54609.
What is 1 GPH in LPH?
- 1 GPH (US) ≈ 3.785 LPH
- 1 GPH (UK) ≈ 4.546 LPH
What is 1 LPH in GPH?
- 1 LPH ≈ 0.2642 GPH (US gallons)
- 1 LPH ≈ 0.22 GPH (UK gallons)
Should I use US or UK gallons?
In the United States, GPH almost always means US gallons per hour. In the UK and some Commonwealth countries, GPH may refer to imperial gallons per hour. If you are using US‑made pumps, filters, or automotive parts, assume US gallons unless the documentation says otherwise.