Square Feet to Square Inches Converter
Convert square feet to square inches — one square foot is 144 square inches. Results update as you type; exact factors shown.
One square foot is 144 square inchs — see the exact factor, not a rounded rule of thumb.
How the square feet to square inches converter works
Areas convert through the square metre. Because the inch is exactly 25.4 mm, a square foot is exactly 0.09290304 m², an acre (43,560 square feet) is exactly 4,046.8564224 m² and a square mile (640 acres) is 2,589,988.110336 m². A hectare is 10,000 m² by definition.
Australia is fully metric under the National Measurement Act 1960; imperial units appear only in trade with the US and in older documents.
Common area conversions
| From | To | Units |
|---|---|---|
| 0.5 ft² | 72 in² | square feet to square inchs |
| 1 ft² | 144 in² | square foot to square inchs |
| 2 ft² | 288 in² | square feet to square inchs |
| 3 ft² | 432 in² | square feet to square inchs |
| 4 ft² | 576 in² | square feet to square inchs |
| 5 ft² | 720 in² | square feet to square inchs |
| 6 ft² | 864 in² | square feet to square inchs |
| 8 ft² | 1,152 in² | square feet to square inchs |
| 10 ft² | 1,440 in² | square feet to square inchs |
| 12 ft² | 1,728 in² | square feet to square inchs |
| 20 ft² | 2,880 in² | square feet to square inchs |
| 50 ft² | 7,200 in² | square feet to square inchs |
Units in this converter and their exact factors
| Unit | Symbol | One unit in square metres |
|---|---|---|
| square millimetre | mm² | 0.000001 square metre |
| square centimetre | cm² | 0.0001 square metre |
| square metre | m² | 1 square metre |
| hectare | ha | 10,000 square metre |
| square kilometre | km² | 1,000,000 square metre |
| square inch | in² | 0.00064516 square metre |
| square foot | ft² | 0.09290304 square metre |
| square yard | yd² | 0.83612736 square metre |
| acre | ac | 4,046.8564224 square metre |
| square mile | mi² | 2,589,988.110336 square metre |
FAQFrequently asked questions about area conversion
How many square inches in a square foot?
Exactly 144 — twelve squared.
What is 10 square feet in square inches?
1,440.
Why 144 and not 12?
Because area is two-dimensional: twelve inches each way gives 12 × 12 = 144.
How many square inches in a square yard?
1,296 — nine square feet at 144 each.
Where does this come up?
Tiling, sheet materials and pressure calculations, where psi is force per square inch.
Where these figures come from
- BIPM — The International System of Units (SI Brochure, 9th edition) — definitions of the base and derived units.
- NIST Special Publication 811 — Guide for the Use of the International System of Units — the exact conversion factors used here.
- National Measurement Institute (NMI) — Australia's national measurement authority.
Last checked: September 2026. Conversion factors are fixed by definition and do not change with tax years or regulations.