gal to fl oz converter
US gallons to US fluid ounces conversions with the math shown
Converter
=
1 gal = 128 fl oz
exact factor: 128
Popular gal to fl oz conversions
0.25 gal = 32 fl oz0.5 gal = 64 fl oz0.75 gal = 96 fl oz1 gal = 128 fl oz1.5 gal = 192 fl oz2 gal = 256 fl oz2.5 gal = 320 fl oz3 gal = 384 fl oz3.5 gal = 448 fl oz4 gal = 512 fl oz4.5 gal = 576 fl oz5 gal = 640 fl oz6 gal = 768 fl oz7 gal = 896 fl oz8 gal = 1,024 fl oz9 gal = 1,152 fl oz10 gal = 1,280 fl oz11 gal = 1,408 fl oz12 gal = 1,536 fl oz13 gal = 1,664 fl oz14 gal = 1,792 fl oz15 gal = 1,920 fl oz16 gal = 2,048 fl oz17 gal = 2,176 fl oz
How it works
Every gal→fl oz page multiplies by the exact factor 128. Definitions, not approximations — the same constants your reference handbook prints.
Frequently asked questions
How many US fluid ounces in 1 US gallon?
Exactly 128 — multiply by 128. The factor is a unit definition, so the answer is exact.
Is the gal→fl oz conversion the same everywhere?
Yes — the factor is fixed by international definition or physical constant, so this site, your textbook and your calculator all agree. Only display rounding differs.
Do you store what I type?
No. The converter runs entirely in your browser — nothing is transmitted, logged or saved.
Related converters
milliliters to US fluid ouncesUS fluid ounces to millilitersliters to US gallons