Convert US gallons to fluid ounces
1 gal (US) = 128 fl oz (US) · 1 fl oz (US) = 0.0078125 gal (US) · Exact by definition
1 gal (US) = 128 fl oz (US)
The same value in other units
- millilitre
- 3785.41 ml
- litre
- 3.78541 l
- cubic metre
- 0.00378541 m³
- US cup
- 16 cup (US)
- imperial gallon
- 0.832674 gal (UK)
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Volume
US gallons to fluid ounces: conversion table
| US gallon | US fluid ounce |
|---|---|
| 1 gal (US) | 128 fl oz (US) |
| 2 gal (US) | 256 fl oz (US) |
| 3 gal (US) | 384 fl oz (US) |
| 5 gal (US) | 640 fl oz (US) |
| 10 gal (US) | 1280 fl oz (US) |
| 20 gal (US) | 2560 fl oz (US) |
| 25 gal (US) | 3200 fl oz (US) |
| 50 gal (US) | 6400 fl oz (US) |
| 100 gal (US) | 12800 fl oz (US) |
| 250 gal (US) | 32000 fl oz (US) |
| 500 gal (US) | 64000 fl oz (US) |
| 1000 gal (US) | 128000 fl oz (US) |
| US fluid ounce | US gallon |
|---|---|
| 1 fl oz (US) | 0.0078125 gal (US) |
| 2 fl oz (US) | 0.015625 gal (US) |
| 3 fl oz (US) | 0.0234375 gal (US) |
| 5 fl oz (US) | 0.0390625 gal (US) |
| 10 fl oz (US) | 0.078125 gal (US) |
| 20 fl oz (US) | 0.15625 gal (US) |
| 25 fl oz (US) | 0.195313 gal (US) |
| 50 fl oz (US) | 0.390625 gal (US) |
| 100 fl oz (US) | 0.78125 gal (US) |
| 250 fl oz (US) | 1.95313 gal (US) |
| 500 fl oz (US) | 3.90625 gal (US) |
| 1000 fl oz (US) | 7.8125 gal (US) |
How the conversion works
fl oz (US) = gal (US) × 128
Both units are defined exactly, so the precision of the US gallons to fluid ounces result depends only on the number of decimal places you choose.
METHOD AND SOURCES
Where the conversion factors come from
Results are calculated from the unit definitions stored in the converter, not copied from a lookup table. For exact units, every value in the table follows from the same factor shown in the formula above.
- BIPM — SI Brochure
The official definitions of the International System of Units (SI).
- NIST SP 811 — Conversion factors
Conversion-factor tables for SI and non-SI units.
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