Convert Square Feet to Square Inches
1 square foot (ft²) equals 144 square inches (in²).
1 ft² = 144 in²
Type in either box. Scientific notation works: 1.5e-3.
Converting a list? Use the bulk square foot to square inch converter to paste a column from Excel.
How to Convert Square Foot to Square Inch
- 1 ft² = 144 in²
- 1 in² = 0.006944444444 ft²
- Example: convert 15 ft² to in²: 15 ft² = 15 × 144 in² = 2160 in²
Formula
in² = ft² × 144
Derivation from SI units:
- 1 ft² = (0.3048 m)² = 0.09290304 m²
- 1 in² = (0.0254 m)² = 6.4516 × 10⁻⁴ m² = 6.4516 cm²
- 1 ft² = 0.09290304 m² ÷ 0.00064516 m² per in² = 144 in²
Both units are defined exactly, so the factor is exact. Square Foot definition: square foot; Square Inch definition: square inch.
Worked examples
- 1 ft² is exactly 144 in².
1 ft² × 144 = 144 in² - A 4 ft² filter face is 576 in².
4 ft² × 144 = 576 in²
Square Foot to Square Inch conversion table
| Square Feet (ft²) | Square Inches (in²) |
|---|---|
| 0.1 ft² | 14.4 in² |
| 0.25 ft² | 36 in² |
| 0.5 ft² | 72 in² |
| 1 ft² | 144 in² |
| 2 ft² | 288 in² |
| 4 ft² | 576 in² |
| 5 ft² | 720 in² |
| 10 ft² | 1440 in² |
| 25 ft² | 3600 in² |
| 50 ft² | 7200 in² |
| 100 ft² | 14400 in² |
| 200 ft² | 28800 in² |
| 500 ft² | 72000 in² |
| 1000 ft² | 144000 in² |
| 1500 ft² | 216000 in² |
| 2000 ft² | 288000 in² |
| 2500 ft² | 360000 in² |
| 5000 ft² | 720000 in² |
| 43560 ft² | 6272640 in² |
Where it's used
US areas in square feet are converted to square inches for force = pressure (psi) × area calculations and small-part design.
Square Foot to other area units
| Conversion | 1 ft² equals |
|---|---|
| square foot to square meter | 0.09290304 m² |
| square foot to square centimeter | 929.0304 cm² |
| square foot to square millimeter | 92903.04 mm² |
| square foot to square inch | 144 in² |
Frequently asked questions
How many square inches are in a square foot?
Exactly 144 (12 × 12).
How many square inches are in 1 square foot?
1 ft² = 144 in².
How do I convert square feet to square inches?
Multiply the value in ft² by 144. For example, 15 ft² × 144 = 2160 in².
Is the ft² to in² conversion exact?
Yes. Both units are defined exactly, and 1 ft² is exactly 144 in².
Sources
- Guide for the Use of the International System of Units (SI), NIST Special Publication 811, 2008 Edition, National Institute of Standards and Technology , Appendix B.8, "square foot (ft²)".
- Guide for the Use of the International System of Units (SI), NIST Special Publication 811, 2008 Edition, National Institute of Standards and Technology , Appendix B.8, "square inch (in²)".
Last reviewed: . Factors are stored exactly and computed with 50-digit decimal arithmetic. See how we verify conversion factors.
Cite this page
APA
Scientific Converters. (2026, October 15). Convert Square Feet to Square Inches. Retrieved October 17, 2026, from https://scientificconverters.com/area/square-feet-to-square-inches/
IEEE
Scientific Converters, "Convert Square Feet to Square Inches," scientificconverters.com. Accessed: Oct. 17, 2026. [Online]. Available: https://scientificconverters.com/area/square-feet-to-square-inches/