Convert Area Units
Area Converter
Area Conversion Chart
Key relationships between area units. The SI unit is the square meter (m²).
Metric (SI)
| 1 km² | = | 1,000,000 m² | exact |
| 1 ha | = | 10,000 m² | exact |
| 1 m² | = | 10,000 cm² | exact |
| 1 cm² | = | 100 mm² | exact |
Imperial / US
| 1 sq mile | = | 640 acres | exact |
| 1 acre | = | 43,560 sq ft | exact |
| 1 sq yard | = | 9 sq ft | exact |
| 1 sq foot | = | 144 sq in | exact |
Cross-System (Exact)
| 1 sq in | = | 6.4516 cm² | exact |
| 1 sq ft | = | 0.09290304 m² | exact |
| 1 acre | = | 4,046.8564224 m² | exact |
| 1 sq mile | = | 2.58999 km² | |
| 1 ha | = | 2.47105 acres |
All cross-system area factors are exact, derived by squaring the length factors from the International Yard and Pound Agreement (1959). 1 inch = 2.54 cm exactly, therefore 1 sq inch = 2.54² = 6.4516 cm² exactly.
About Area Units
Real Estate & Property
Residential properties use sq ft (US) or m² (metric). Houses: a typical US home is 1,500–2,500 ft² (139–232 m²). Land plots use acres (US/UK) or hectares (metric). 1 acre ≈ 75% of a football field.
Agriculture & Land
Farms use hectares (metric) or acres (US/UK/Australia). 1 hectare = 2.471 acres = 100 m × 100 m. Average US farm: ~180 hectares. Large geographic areas use km² or sq miles (1 sq mile = 640 acres).
Science & Engineering
The SI unit is the square meter (m²). Cross-system area factors are the SQUARE of the length factors: 1 ft = 0.3048 m, but 1 ft² = 0.3048² = 0.0929 m². This squaring effect makes area ratios much larger than length ratios.
Area conversion factors are the square of the corresponding length factors. This is why 1 foot = 0.3048 m but 1 square foot = 0.0929 m², not 0.3048 m². The same principle applies to all cross-system conversions.
Popular Area Conversions
Acre Conversions
Square Foot & Meter
Hectare & Large-Scale
Conversion Charts & Tables
Printable charts and reference tables for area conversions:
Acres & Hectares
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Frequently Asked Questions
How many square feet are in an acre?
One acre contains exactly 43,560 square feet. To visualize, an acre is roughly the size of a football field without the end zones (about 48,000 sq ft). In metric terms, one acre equals approximately 4,047 square meters or about 0.405 hectares.
What is the difference between an acre and a hectare?
Both measure land area, but in different systems. One hectare equals 10,000 square meters (a 100m x 100m square), while one acre equals 4,047 square meters. A hectare is about 2.47 times larger than an acre. Hectares are used internationally; acres are used primarily in the US, UK, and former British colonies.
How do I convert square meters to square feet?
Multiply the square meter value by 10.7639. For example, 100 sq m = 1,076.39 sq ft. This conversion is essential when comparing international property listings (metric) with US or UK listings (imperial). For a quick estimate, multiply by 11 and subtract 3%.
Why are there so many different area units?
Different area units evolved for different scales and contexts. Square inches and centimeters suit small objects, square feet and meters work for rooms and buildings, acres and hectares measure farmland, and square miles or kilometers describe cities and countries. Each unit avoids inconveniently large or small numbers at its intended scale.
Why is the area conversion factor different from the length factor?
Because area is two-dimensional. The area factor is the square of the linear factor. For example, 1 foot = 0.3048 meters, but 1 square foot = 0.3048 squared = 0.0929 square meters. This means the difference between units is amplified when converting area — a 3.28:1 length ratio becomes a 10.76:1 area ratio.
Related Converter Categories
- Length Converter — Area factors = length factors squared
- Volume Converter — Volume = area × height
