GPM to LPS Conversion Factor for Philippine Pump Specs

The exact conversion factor is 0.0630902: multiply any GPM figure by this number to get the equivalent flow in liters per second. For a quick mental check in the field, divide GPM by 15.85 and you land within half a percent of the exact figure, close enough for a first pass before a formal quotation.

Working the factor both ways matters because Philippine distributors, plumbing design consultants, and imported pump datasheets do not agree on a single unit. A 100 GPM duty point converts to 6.309 LPS, a 250 GPM duty point converts to 15.77 LPS, and a 500 GPM duty point converts to 31.5 LPS. On the larger end, flows are commonly reported in cubic meters per hour instead of liters per second: multiply LPS by 3.6 to reach m3/hr, so that same 500 GPM point is 113.6 m3/hr. Keep the raw GPM figure on file alongside the converted value when you request a quotation. JOHOB Hardware Trading's pumping and pressure systems range, covering booster, transfer, and submersible pumps along with VFD duplex panels, is specified and quoted in whichever of these three units your project's mechanical drawings already use, so the conversion only needs to happen once, not every time a document changes hands.

Not every gallon is the same size, and this is where GPM to LPS conversions go wrong on Philippine projects referencing equipment originally specified against older Commonwealth engineering standards. A US gallon equals 3.785411784 liters, which is where the 0.0630902 factor comes from. An Imperial gallon equals 4.54609 liters, about 20 percent larger, giving a different factor of 0.0757682 liters per second for every Imperial GPM. Apply the US factor to an Imperial-rated pump curve and you will under-convert the flow by roughly a sixth, enough to undersize a booster pump for a mid-rise building.

Before converting any imported datasheet, confirm which gallon standard the manufacturer used. Most pumps distributed through Philippine industrial suppliers, including JOHOB Hardware Trading, are specified in US gallons per minute, but older or UK-origin equipment occasionally still lists Imperial GPM. When in doubt, ask for the LPS or m3/hr figure directly from the test certificate rather than back-calculating from GPM, since the certificate removes the gallon-standard ambiguity entirely.

Philippine mechanical and plumbing design follows the National Plumbing Code of the Philippines (NSPC) and the National Building Code (NBC), both of which specify flow demand in liters per second for fixture unit calculations, while imported pump curves and many overseas manufacturer catalogs default to GPM, and utility-scale pump stations often report output in cubic meters per hour for billing and metering purposes. A single commercial project can therefore carry all three units across its documents: the plumbing engineer's fixture unit load in LPS, the pump manufacturer's performance curve in GPM, and the building's water utility connection sized in m3/hr.

Buyers who do not reconcile these units before issuing a purchase order risk ordering a pump sized to the wrong duty point, which either starves upper floors of pressure or wastes electricity running an oversized motor. JOHOB Hardware Trading's buying guides, including this one, are written against NSPC and NBC flow and pressure terminology specifically so a facilities engineer or procurement officer can cross-check a quotation against the code requirement without converting units twice. Confirming the unit convention with your supplier before finalizing a duty point takes a few minutes and avoids a reorder that can add weeks to a project timeline.

JOHOB Hardware Trading supplies pumping and pressure systems nationwide across NCR, Luzon, Visayas, Mindanao, and PEZA/SBMA/Clark locations, and converts every quoted duty point into the unit specified in the project documents as part of the RFQ response.

Flow rate is only half of a pump duty point. The other half, head or pressure, has its own unit mismatch problem. One psi equals 0.0689476 bar, and one psi equals approximately 0.7031 meters of water column at standard temperature, so a pump rated for 60 psi discharge pressure is also rated for roughly 4.14 bar or 42.2 meters of head. Imported pump curves from European-standard manufacturers plot head in meters, American-standard curves plot it in feet or psi, and Philippine plumbing drawings typically specify required pressure in either psi or meters of head depending on the consulting engineer's background.

Converting feet to meters is a straight multiplication by 0.3048, so 140 feet of head becomes 42.7 meters, close to the 42.2 meter figure above since both describe a similar duty point from different starting units. Always convert both flow and head together rather than one at a time, since a pump curve is a two-axis chart and an error on either axis changes which point on the curve your system actually operates at. Our guide on how to size a booster pump for a commercial building works through flow and head together for exactly this reason.

Consider a sample duty point of 150 GPM at 60 psi discharge pressure, a size common to a mid-rise commercial booster pump application.

Converting flow first: 150 GPM multiplied by 0.0630902 gives 9.46 LPS, also 34.1 m3/hr after multiplying by 3.6.
Converting pressure next: 60 psi multiplied by 0.0689476 gives 4.14 bar, equivalent to about 42.2 meters of water column using the 0.7031 meters-per-psi factor.

The complete metric duty point is therefore 9.46 LPS at 42.2 meters of head, or equivalently 34.1 m3/hr at 4.14 bar, and either pairing should appear on the pump curve your supplier proposes. Write out all four figures, GPM, LPS, and m3/hr for flow, and psi, bar, and meters for head, on the purchase request so there is no ambiguity between what the plumbing drawing specifies and what the pump manufacturer's curve shows. This is the same worked-example approach JOHOB Hardware Trading's pump sizing guides use for booster pump sizing, condominium pump horsepower, and pressure tank sizing, so a procurement officer comparing multiple guides arrives at consistent, cross-checkable numbers instead of a different rounding convention on every page. A duty of this size is often handled as a duplex or triplex set from our commercial booster pumps range rather than a single pump, so the per pump flow is the total divided across the running units, with one unit on standby. Our guide on when a VFD is worth it versus a fixed speed pump covers the control side of the same decision. When requesting a quote from JOHOB Hardware Trading, state the duty point in whichever unit your project specification uses; the RFQ response converts and confirms the figure within 1 business day, before any lead time (21 to 35 days ex-stock, or 45 to 90 days made-to-order) starts running.

Once a duty point is converted and double-checked, the next step is getting an accurate quotation rather than a generic one. JOHOB Hardware Trading responds to RFQs within one business day and quotes pumping and pressure systems, including booster, transfer, and submersible pumps with our VFD duplex control panels, against whichever unit set, GPM, LPS, or m3/hr for flow, psi, bar, or meters for head, appears on your mechanical drawings. Standard lead times run 21 to 35 days for ex-stock equipment and 45 to 90 days for made-to-order configurations, so confirming the duty point correctly the first time avoids a lead-time reset.

Pricing is quote-based and not published publicly, 12 percent VAT applies for VAT-registered buyers, and PEZA or SBMA-registered locators and exporters qualify for zero-VAT treatment on eligible purchases. Coverage is nationwide across NCR, Luzon, Visayas, Mindanao, and the PEZA, SBMA, and Clark economic zones. Equipment supplied carries ISO 9001 manufacturer quality certification, TUV SUD testing, CE marking where applicable, and ASME compliance for pressure vessels where applicable, from a vetted overseas manufacturer partner. For water storage sized to the same flow duty point, JOHOB's sister brand TankSmith (tanksmith.com) supplies the modular tank side of the same system.

Submitting the converted duty point with the RFQ, rather than the raw datasheet figure, shortens the quote cycle because it removes one back-and-forth clarification step before a matching pump and piping, valves, and stainless steel flexible hose can be confirmed. Process duties like commercial laundry water requirements in the Philippines get the same unit restatement on the quotation.

• Guide: How to Size a Booster Pump
• Pumping and Pressure Systems
• Commercial Booster Pumps
• Guide: VFD vs Fixed-Speed Pumps
• Guide: Commercial Laundry Water Requirements
• Electrical Panels and Controls
• Water Storage Tanks

Reviewed: October 2026