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US gallons to Cubic feet (gal (US) to ft³)
Convert US gallons to cubic feet: 1 gal (US) = 0.133681 ft³. Exact conversion factor, formula, 22-row table and worked examples, with JSON API and MCP access.
Formula
1 gal (US) = 0.133681 ft³
cubic feet = US gallons × 0.1336805556 — reverse: US gallons = cubic feet × 7.480519481
The factor is derived from the SI definitions of both units (base unit: L) as listed in NIST SP 811; results on this page are shown to 6 significant figures, the API returns up to 12.
Worked examples
- 5 gal (US) = 0.668403 ft³
- 12.5 gal (US) = 1.67101 ft³
- 100 gal (US) = 13.3681 ft³
US gallons to cubic feet conversion table
| US gallons (gal (US)) | Cubic feet (ft³) |
|---|---|
| 1 | 0.133681 |
| 2 | 0.267361 |
| 3 | 0.401042 |
| 4 | 0.534722 |
| 5 | 0.668403 |
| 6 | 0.802083 |
| 7 | 0.935764 |
| 8 | 1.06944 |
| 9 | 1.20312 |
| 10 | 1.33681 |
| 15 | 2.00521 |
| 20 | 2.67361 |
| 25 | 3.34201 |
| 30 | 4.01042 |
| 40 | 5.34722 |
| 50 | 6.68403 |
| 75 | 10.026 |
| 100 | 13.3681 |
| 200 | 26.7361 |
| 250 | 33.4201 |
| 500 | 66.8403 |
| 1000 | 133.681 |
FAQ
How many cubic feet are in one gallon?
1 gal (US) = 0.133681 ft³. The factor comes from the SI definitions of both units (NIST SP 811 / BIPM), so it is exact or correct to at least 10 significant figures.
What is the formula to convert US gallons to cubic feet?
Multiply the value in US gallons by 0.1336805556: cubic feet = US gallons × 0.1336805556. For example, 5 gal (US) = 0.668403 ft³.
How do I convert cubic feet back to US gallons?
Multiply by the inverse factor 7.480519481 (US gallons = cubic feet × 7.480519481), or use the cubic feet-to-US gallons page.
Related conversions
Machine access
- API:
GET https://tttkmbb.com/api/v1/convert?value=5&from_unit=gal_us&to_unit=ft3 - MCP: server
https://tttkmbb.com/mcp, toolconvert_unitswith{"value":5,"from_unit":"gal_us","to_unit":"ft3"} - Markdown: https://tttkmbb.com/conversion/gallons-to-cubic-feet.md · JSON: https://tttkmbb.com/conversion/gallons-to-cubic-feet.json (add
?value=for a result) · Units: /api/v1/units?quantity=volume - OpenAPI operationId:
convert_units. Freshness:static. Authentication: none.