US gallons per minute to Liters per minute Calculator

Direct answer

Multiply the entered us gallons per minute value by 3.785411784 to express it in liters per minute (L/min). This converts US gallon per minute (gpm) to liter per minute (L/min) within the documented flow rate family.

Variables and formula

• US gallons per minute (gpm): the source value measured in US gallon per minute.
• Liters per minute (L/min): the same quantity expressed in liter per minute.
• Conversion factor: 3.785411784 liters per minute per US gallon per minute.

Liters per minute = US gallons per minute × 3.785411784

The generator emits numeric factors with at most 15 significant digits. Calculator results keep up to 10 significant digits for display; this formatting does not increase the precision of the measurement.

Unit definitions and named variants

Source unit: US gallon per minute (gpm). One U.S. liquid gallon per minute equals exactly 3.785411784 litres per minute because the U.S. gallon is exactly 231 international cubic inches. Named variant used: U.S. liquid gallon only; not Imperial gallon. Reference: National Institute of Standards and Technology: NIST Guide to the SI, Appendix B.9: Factors for Units Listed by Kind of Quantity or Field of Science; National Institute of Standards and Technology: NIST Handbook 44 (2026), Appendix C: General Tables of Units of Measurement.

Target unit: liter per minute (L/min). A litre per minute is a volumetric flow of one litre during one minute. Named variant used: Volumetric flow; no standard-condition normalization. Reference: Bureau International des Poids et Mesures: The International System of Units (SI), 9th edition, version 4.01.

The gpm-to-L/min direction remains inside the flow rate quantity; it changes the unit label and numerical scale, not the kind of quantity being measured.

Relationship and precision

The named unit relationships are defined or exact, so the conversion is exact before display rounding and source-measurement uncertainty.

• gpm relationship: The terminating base factor is exact for the U.S. liquid gallon and international inch.
• L/min relationship: The base factor is exactly 1 by the family base-unit choice.

To audit the factor through the family base unit, divide the raw dataset factors 3.785411784 by 1. The generator emits that quotient once at 15 significant digits as the canonical direct factor 3.785411784; runtime calculations do not divide the already-emitted base factors again.

Reproducible example

For 10 us gallons per minute, 10 × 3.785411784 = 37.85411784 liters per minute. Repeating the same multiplication with the stated factor reproduces the displayed conversion before interface rounding.

Directional scale check

Because one US gallon per minute contains 3.785411784 liters per minute, the target number is larger than the source number for every positive input. Zero maps to zero, while negative inputs are rejected because this family models non-negative magnitudes.

Interpretation

Read the result as liters per minute, not us gallons per minute. A value entered as gpm leaves the calculator labelled L/min; this directional distinction matters even when the two units describe the same flow rate quantity.

Assumptions and limitations

• Only non-negative flow magnitudes are accepted; direction is outside this family.
• Gas flows quoted at standard or actual conditions require temperature and pressure normalization that this unit-only converter does not perform.
• A conversion does not add significant figures to the source measurement.

Common mistakes

• Imperial gpm uses a different gallon and must not use this factor.
• Use uppercase L to avoid confusion with the numeral 1.

Continue within the Flow Rate family

See the Flow Rate conversion hub for its five-unit reference table and all 20 directed routes.

• Reverse the direction: Liters per minute to US gallons per minute
• Compare another flow rate route: US gallons per minute to Liters per second
• Compare another flow rate route: US gallons per minute to Cubic meters per hour
• Compare another flow rate route: US gallons per minute to Cubic feet per minute
• Compare another flow rate route: Liters per minute to Liters per second

Assumptions

• The entered value uses us gallons per minute exactly as labelled.
• Only non-negative flow magnitudes are accepted; direction is outside this family.
• Rounding and measurement uncertainty remain the user's responsibility.

Sources and methodology

CalcMotive publishes the formula and assumptions so you can decide whether the estimate fits your use case. See our methodology standards.

• The International System of Units (SI), 9th edition, version 4.01; Bureau International des Poids et Mesures; accessed Aug 7, 2026
• NIST Guide to the SI, Appendix B.9: Factors for Units Listed by Kind of Quantity or Field of Science; National Institute of Standards and Technology; accessed Aug 7, 2026
• NIST Handbook 44 (2026), Appendix C: General Tables of Units of Measurement; National Institute of Standards and Technology; accessed Aug 7, 2026