Square Foot to Square Kilometer (ft² to km²)
Result
9.290304e-8 Square Kilometer
Formula
km² = ft² × 9.290304e-8
1 ft² = 9.290304e-8 km², and 1 km² = 10,763,910.42 ft².
Area factors are the square of the length factor: 1 ft = 0.3048 m, so 1 ft² = 0.3048² = 0.09290304 m². The acre is 43,560 ft² (4,046.8564224 m²) and the hectare 10,000 m².
Worked examples
- 1 ft² × 9.290304e-8 = 9.290304e-8 km²
- 10 ft² × 9.290304e-8 = 9.290304e-7 km²
- 100 ft² × 9.290304e-8 = 0.000009290304 km²
Common mistakes
- Do not apply a length factor to an area: 100 m² is 1,076.39 ft², not 328 ft² (100 × 3.28).
- A plot described as "20 × 30 ft" is 600 ft²; convert each side to metres first or convert the area afterwards — never just one side.
Square Foot to Square Kilometer table
| Square Foot (ft²) | Square Kilometer (km²) |
|---|---|
| 1 | 9.290304e-8 |
| 2 | 1.8580608e-7 |
| 5 | 4.645152e-7 |
| 10 | 9.290304e-7 |
| 20 | 0.000001858061 |
| 50 | 0.000004645152 |
| 100 | 0.000009290304 |
| 1,000 | 0.00009290304 |
The units
- Square Foot (ft²)
- A square one foot on each side: exactly 0.09290304 m².
- Square Kilometer (km²)
- 1 Square Kilometer = 1,000,000 Square Meter.
Sources for these factors
- Handbook 44 (2024), Appendix C: General Tables of Units of Measurement — NIST
- Guide for the Use of the International System of Units (SP 811), Appendix B: conversion factors — NIST
Last reviewed against these sources. An automated check recomputes every factor from its definition on each build. How we check accuracy