Flow calculator: gpm and MGD

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Answer: 0.864 MGD

gpm is gallons per minute, and a day has 1,440 minutes (24 × 60). First find the gallons in a day.
600 gpm × 1,440 min/day = 864,000 gal/day.
Divide by 1,000,000 to get million gallons a day: 864,000 ÷ 1,000,000 = 0.864 MGD.

Exam-practice math only. It is not an instruction for a real plant, well or tank: for that, follow your system's procedures and ask your supervisor.

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The numbers it uses

A day has 1,440 minutes (24 × 60), the number the formulas use to turn a per-minute flow into a per-day flow.[1]

One million gallons (MG) is 1,000,000 gallons.[1]

Sources

Tennessee Dept. of Environment and Conservation, Fleming Training Center: Tennessee Operator Certification Formula Manual, Water Treatment Formulas & Conversions, Coagulation/Flocculation: Detention Time, min = (Volume, gal)(1440 min/day) ÷ Flow, gpd; Unit Conversion Factors, Volume: 1 MG = 1,000,000 gal (read November 13, 2026)

Reviewed November 13, 2026. Published by OperadorListo. The sources above are the authority. This is a summary in our own words: check the source before you act on it.