Unit converter
Gallons (US) to Fluid ounces (US)
Instant conversion in your browser — volume.
Tip: enter the values one by one — 40 30 55 20 — and you get the total and the average.
1 gal = 128 fl oz
Quick table Gallons (US) → Fluid ounces (US)
| gal | fl oz |
|---|---|
| 1 | 128 |
| 5 | 640 |
| 10 | 1,280 |
| 25 | 3,200 |
| 50 | 6,400 |
| 100 | 12,800 |
| 500 | 64,000 |
| 1,000 | 128,000 |
All unit families
- Lengthmm · cm · m · km · in · ft · yd · miAlmost the whole world measures length in metres. The exceptions are narrow but stubborn: the United States uses feet and inches for everyday distances, and the United Kingdom still posts road signs in miles while selling timber in millimetres.
- Weight / Massmg · g · kg · t · oz · lb · stThe kilogram is the base unit, and until 2019 it was the last one still defined by a physical object: a platinum-iridium cylinder kept near Paris. It is now defined through the Planck constant, so it can be reproduced in any properly equipped laboratory.
- Temperature°C · °F · KTemperature is the one family here that is not a multiplication. Celsius and Fahrenheit have different zero points as well as different step sizes, so you need the formula: °F = °C × 9/5 + 32.
- Aream² · km² · ha · ft² · acAreas are where a linear conversion quietly goes wrong. One metre is 3.28 feet, but one square metre is 10.76 square feet — the factor is squared. Converting the sides and forgetting the square is the single most common mistake in this family.
- Speedkm/h · mph · m/s · knFour units, four different worlds. Kilometres per hour on European roads, miles per hour in the US and UK, metres per second in physics and weather bulletins, knots at sea and in the air.
- Times · min · h · d · wk · mo · yrSeconds, minutes, hours, days and weeks convert exactly. Months and years do not, and no converter can make them.
- Digital storagebit · B · KB · MB · GB · TBDigital storage has two conflicting definitions of the same prefixes, and almost every confusion about file sizes comes from that.
About this conversion
Volume conversion: 1 gallons (us) (gal) equals 128 fl oz. As a practical reference, 150 gal = 19,200 fl oz — helpful for cooking, fuel and liquid packaging.
| gal | fl oz |
|---|---|
| 150 | 19,200 |
Frequently asked questions
How do you convert gallons (us) to fluid ounces (us)?
To go from gal to fl oz: multiply by 128 (1 gal = 128 fl oz). Example: 3 gal = 384 fl oz. The converter above runs the math live as you type.
How much is 150 gallons (us) in fluid ounces (us)?
150 gal equals 19,200 fl oz. For other values, use the quick table or type your own number into the converter.
What are US gallons (gal)?
The US gallon is 3.785 liters (the UK imperial gallon is larger, 4.546 l). Fuel prices and milk jugs in the US use it — filling a 15-gallon tank means about 57 liters.
What are fluid ounces (fl oz)?
The US fluid ounce is 29.57 ml, one sixteenth of a pint. Cocktail recipes, soda cans (12 fl oz) and cosmetics use it — despite the name, it measures volume, not weight.