cubic meters to gallons

A pool builder working from a metric plan — 50 m³, say — and an American pool-supply catalog that sells chlorine by the gallon will meet at 264.172052358, the exact number of US gallons in a cubic meter. The number is a reciprocal of the gallon's 231 in³ definition and the 1959 inch, so it carries no approximation; it just looks alarming because it is built from an ancient English volume standard against the modern metric cube.

By EnginStack Engineering Team | Verified by engineers, built on NIST metrology standards About →
cubic meters
50 gallons
50 cubic meters = 13,208.60261791 gallons 50 gallons = 0.18927059 cubic meters

Authority: NIST SP 811 (SI usage guide) and the 1959 International Yard and Pound Agreement. The coefficient above is a defined value — it does not come from measurement and carries no uncertainty.

cubic meters to gallons

One cubic meter is exactly 264.172052358 US gallons — the factor is exact because both units are legally defined, and it is the reciprocal of 0.003785411784. The engineering situations where this matters are almost always chemical-dosing: pool chlorination, water-treatment alum feed, cooling-tower biocide, all spec the treatment in gallons while the tank volume is in cubic meters. Get the dose per m³ wrong by forgetting the 264, and the treatment is off by a factor of more than two hundred.

gallons = cubic meters × 264.172052358
1 cubic meter = 264.172052358 US gallons — the reciprocal of the 231 in³ gallon
The factor is exact: 1 / 0.003785411784.

Common cubic meters to gallons Conversions

cubic metersgallonsContext
1 m³264.2 galOne cubic meter — the metric anchor.
50 m³13,209 galA backyard swimming pool.
100 m³26,417 galA large commercial pool.
1,000 m³264,172 galA municipal reservoir segment.
10,000 m³2,641,720 galA fire-protection water tank.

Engineering Context

The gallons to cubic meters page inverts this constant. It sits in the volume family next to liters to cubic meters and gallons to liters — the latter being the everyday version of the same transatlantic bridge. Water-treatment dosing ties this page to the density and weight families.

More: gal to m³ · L to m³ · gal to L · Volume Hub

Related Unit Converters

Gallons To Cubic Meters Liters To Cubic Meters Gallons To Liters Volume Converters

Frequently Asked Questions

How many gallons are in a cubic meter?

Exactly 264.172052358 US gallons. It is the reciprocal of the US gallon's volume in cubic meters: 1 gal = 231 in³ = 0.003785411784 m³, so 1 m³ = 1 / 0.003785411784 = 264.172052358 gal.

Why does pool chemistry use gallons when pool volume is metric?

Because dosing products are sold in the US market with instructions in gallons, while pool designs from metric countries quote volume in cubic meters. The mismatch is exactly why this converter exists — dose per m³ and dose per gallon are 264 apart.

How accurate is '1 m³ = 264 gallons'?

It is within 0.07% — fine for estimates. For chemical dosing, use the full factor 264.172052358, since a 0.07% error in a treatment rate can compound over large water volumes.