5 US gallons to US fluid ounces
5 gal = 640 fl oz. Change the amount below, or read the formula and the reference table further down.
5 US gallons equals
US fluid ounces
1 gal = 128 fl oz
The formula
US gallons and US fluid ounces both measure volume from the same zero, so a single multiplier does the job.
fl oz = gal × 128
Going the other way? Convert US fluid ounces to US gallons.
US gallons to US fluid ounces table
Values either side of 5 gal.
| US gallons (gal) | US fluid ounces (fl oz) |
|---|---|
| 0 | 0 |
| 0.5 | 64 |
| 1 | 128 |
| 1.5 | 192 |
| 2 | 256 |
| 2.5 | 320 |
| 3 | 384 |
| 3.5 | 448 |
| 4 | 512 |
| 4.5 | 576 |
| 5 | 640 |
| 5.5 | 704 |
| 6 | 768 |
| 6.5 | 832 |
| 7 | 896 |
| 7.5 | 960 |
| 8 | 1,024 |
| 8.5 | 1,088 |
| 9 | 1,152 |
| 9.5 | 1,216 |
| 10 | 1,280 |
Questions people ask
- How many US fluid ounces are in a US gallon?
- One US gallon equals 128 US fluid ounces.
- How do I convert US gallons to US fluid ounces by hand?
- Multiply the number of US gallons by 128. For a rough check, 128 is close enough for most everyday use.
- What is 5 US gallons in US fluid ounces?
- 5 US gallons is 640 US fluid ounces.
Calcuit generates this page from a unit table, so the factors here match every other page on the site.