Volume

Convert gallons to fluid ounces

1 us gallon equals 128 us fluid ounces. Enter a value below to convert instantly.

1 gal (US)
128 fl oz (US)

Multiply the number of us gallons by 128 to get us fluid ounces. How this is calculated

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Need the other direction? Convert us fluid ounce to us gallon →

Formula

Multiply the number of us gallons by 128 to get us fluid ounces.

Step by step

  1. Start with 1 gal (US).
  2. Multiply by the conversion factor 128.
  3. 1 × 128 = 128 fl oz (US).

US Gallons to US Fluid Ounces conversion table

Conversion table from US Gallons to US Fluid Ounces
US Gallons (gal (US)) US Fluid Ounces (fl oz (US))
1 128
2 256
3 384
5 640
10 1,280
20 2,560
50 6,400
100 12,800
500 64,000
1,000 128,000

Convert US Gallon to other volume units

1 gal (US) expressed in every other volume unit on this site.

  • Liter L 3.7854118
  • Milliliter mL 3,785.4118
  • Centiliter cL 378.54118
  • Deciliter dL 37.854118
  • Dekaliter daL 0.37854118
  • Hectoliter hL 0.037854118
  • Kiloliter kL 0.0037854118
  • Microliter µL 3,785,411.8
  • Nanoliter nL 3,785,411,800
  • Picoliter pL 3,785,411,800,000
  • Femtoliter fL 3.7854118e+15
  • Attoliter aL 3.7854118e+18
  • Megaliter ML 0.0000037854118
  • Gigaliter GL 3.7854118e-9
  • Petaliter PL 3.7854118e-15
  • Exaliter EL 3.7854118e-18
  • Dekastere dast 0.00037854118
  • Metric Cup cup (metric) 15.141647
  • Metric Tablespoon tbsp (metric) 252.36079
  • Metric Teaspoon tsp (metric) 757.08236
  • Cubic Meter 0.0037854118
  • Cubic Kilometer km³ 3.7854118e-12
  • Cubic Centimeter cm³ 3,785.4118
  • Cubic Millimeter mm³ 3,785,411.8
  • Drop gtt 75,708.236
  • Cubic Mile mi³ 9.0816858e-10
  • Cubic Yard yd³ 0.0049511317
  • Cubic Foot ft³ 0.13368056
  • Cubic Inch in³ 231
  • Hundred Cubic Feet ccf 0.0013368056
  • Ton Register RT 0.0013368056
  • Acre-foot ac·ft 0.0000030688833
  • Acre-inch ac·in 0.000036826599
  • Cord cord 0.0010443793
  • Cord Foot cord ft 0.0083550347
  • Board Foot bf 1.6041667
  • US Quart qt (US) 4
  • US Pint pt (US) 8
  • US Cup cup (US) 16
  • US Gill gi (US) 32
  • US Fluid Ounce fl oz (US) 128
  • US Tablespoon tbsp (US) 256
  • US Teaspoon tsp (US) 768
  • US Dessertspoon dstspn (US) 384
  • US Fluid Dram fl dr (US) 1,024
  • US Minim min (US) 61,440
  • US Barrel (oil) bbl (oil) 0.023809524
  • US Barrel (liquid) bbl (liq) 0.031746032
  • US Barrel (federal, beer) bbl (beer) 0.032258065
  • US Hogshead hhd (US) 0.015873016
  • Tun tun 0.003968254
  • US Bushel bu (US) 0.10742088
  • US Peck pk (US) 0.4296835
  • US Dry Gallon gal (US dry) 0.85936701
  • US Dry Quart qt (US dry) 3.437468
  • US Dry Pint pt (US dry) 6.8749361
  • US Barrel (dry) bbl (dry) 0.032738095
  • Imperial Gallon gal (UK) 0.83267418
  • Imperial Quart qt (UK) 3.3306967
  • Imperial Pint pt (UK) 6.6613935
  • Imperial Cup cup (UK) 13.322787
  • Imperial Gill gi (UK) 26.645574
  • Imperial Fluid Ounce fl oz (UK) 133.22787
  • Imperial Tablespoon tbsp (UK) 213.16459
  • Imperial Teaspoon tsp (UK) 639.49377
  • Imperial Fluid Dram fl dr (UK) 1,065.823
  • Imperial Minim min (UK) 63,949.377
  • Imperial Bushel bu (UK) 0.10408427
  • Imperial Peck pk (UK) 0.41633709
  • Imperial Dessertspoon dstspn (UK) 319.74689
  • Imperial Barrel bbl (UK) 0.023129838
  • Acre-foot (US survey) ac·ft (US) 0.0000030688649
  • Cor (Biblical) cor 0.017206417
  • Homer (Biblical) homer 0.017206417
  • Bath (Biblical) bath 0.17206417
  • Hin (Biblical) hin 1.032385
  • Cab (Biblical) cab 3.0971551
  • Log (Biblical) log 12.38862
  • Doe 2.0984519
  • Hop 20.984519
  • Jak 209.84519
  • Mal 0.20984519
  • Seom 0.020984519
  • Earth's Volume V⊕ 3.4953017e-24

About the us gallon

The us gallon (gal (US)) is a US unit of volume.

About the us fluid ounce

The us fluid ounce (fl oz (US)) is a US unit of volume.

Where this conversion is used

Converting us gallons to us fluid ounces comes up when cooking recipes, fuel, beverages, and container capacity. US and Imperial liquid measures differ, so a US cup or gallon is not the same size as its UK counterpart.

Related conversions

Frequently asked questions

How many us fluid ounces are in a us gallon?

One us gallon equals 128 us fluid ounces.

How do you convert us gallons to us fluid ounces?

Multiply the number of us gallons by 128 to get us fluid ounces.

What is 1 us fluid ounce in us gallons?

One us fluid ounce equals 0.0078125 us gallons.

When would I convert us gallons to us fluid ounces?

This conversion is common when cooking recipes, fuel, beverages, and container capacity.

Conversion factors are based on internationally agreed unit definitions. See our methodology and sources for details on how these values are verified.