ft/d
foot per day
Speedexact by definition
The foot per day is exactly 0.3048/86,400 m/s, about 3.53 × 10⁻⁶ m/s. It is the customary unit for hydraulic conductivity in United States groundwater practice, used in Darcy's law and in well and aquifer analysis. The factor is exact by definition.
Watch out: US groundwater literature also uses gallons per day per square foot for the same quantity. One foot per day is about 7.48 gpd/ft², since a cubic foot is 7.48 US gallons.
| 1 ft/d | 0.0000035277778 m/s |
Solvers that use speed