Volume
gal (US)toac·ft
Convert US gallons (gal (US)) to acre-feet (ac·ft).
Factor1 gal (US) = 3.068883e-6 ac·ft
Converter
gal (US)
Accepts numbers or expressions, e.g. 150 + 14.7
Result
ac·ft
Rendered to 6 significant figures.
Formula
Formula
ac·ft = gal (US) × 3.068883e-6
Multiply any value in US gallons by 3.068883e-6 to obtain the value in acre-feet.
Worked example
Convert 100000 gal (US) to ac·ft.
- 01Start with 100000 gal (US).
- 02Multiply by the conversion factor: 100000 × 3.068883e-6 = 0.306888 ac·ft.
Result100000 gal (US) = 0.306888 ac·ft
Conversion table
| gal (US) | ac·ft |
|---|---|
| 1 | 3.0689e-6 |
| 2 | 6.1378e-6 |
| 5 | 1.5344e-5 |
| 10 | 3.0689e-5 |
| 20 | 6.1378e-5 |
| 50 | 0.00015344 |
| 100 | 0.00030689 |
| 200 | 0.00061378 |
| 500 | 0.0015344 |
| 1000 | 0.0030689 |
Reference values rounded to 5 significant figures for display.
FAQ
What is the conversion factor from gal (US) to ac·ft?
1 gal (US) equals 3.068883e-6 ac·ft. To convert, multiply the value in US gallons by 3.068883e-6.
How do I convert 1 gal (US) to ac·ft?
1 gal (US) = 3.06888e-6 ac·ft. For any value, multiply by 3.068883e-6.
How do I convert ac·ft back to gal (US)?
Divide by the same factor — or equivalently, multiply by 325851.4. So 1 ac·ft = 325851 gal (US).
When would I need to convert US gallon to acre-foot?
Volume conversions are used for tank sizing, batch calculations, and bridging between vendor specs (gallons, barrels, ft³) and process documentation (m³, litres).
Is the conversion exact?
The factor shown is precise to at least 7 significant figures. For most process-engineering work this is far better than instrument accuracy. For metrology or trade applications, refer to the relevant national standard (NIST, BIPM, ISO 80000).