sq ft sq m acres hectares
Last reviewed: January 2026
Convert between square feet, square meters, square inches, acres, hectares, and square miles. This calculator runs entirely in your browser — your data stays private, and no account is required.
Area measures the two-dimensional space within a boundary, expressed in square units. The metric system uses square meters (m²) as the base unit, with hectares (10,000 m²) for land measurement, while the U.S. customary system uses square feet for buildings and acres (43,560 sq ft) for land.[1] Converting between metric and imperial area units requires squaring the linear conversion factor — since 1 foot equals 0.3048 meters, 1 square foot equals 0.3048² = 0.0929 square meters.[2] In real estate, one acre is roughly the size of a football field without the end zones, and 640 acres make up one square mile (a "section" in the U.S. Public Land Survey System).[3] Use the Length Converter for linear distance conversions.
Real estate in the US uses square feet for homes and acres for land. Commercial real estate uses square footage for interior spaces and sometimes acres for site area. Agricultural land is measured in acres in the US and hectares internationally. One acre was historically the amount of land a yoke of oxen could plow in one day. An acre is not a square shape — it is simply a unit of area that can be any shape. A perfectly square acre would measure about 208.7 feet per side.
| Unit | Square Feet | Square Meters | Acres |
|---|---|---|---|
| 1 sq ft | 1 | 0.0929 | 0.0000230 |
| 1 sq meter | 10.764 | 1 | 0.000247 |
| 1 acre | 43,560 | 4,047 | 1 |
| 1 hectare | 107,639 | 10,000 | 2.471 |
| 1 sq mile | 27,878,400 | 2,589,988 | 640 |
Area measurement — quantifying two-dimensional space — uses different unit systems depending on the field, region, and scale of measurement. Converting between square feet, square meters, acres, hectares, and other units is essential for real estate, agriculture, construction, land management, and international commerce.
The metric system scales cleanly by powers of 10: 1 square meter (m²) = 10,000 square centimeters (cm²), 1 hectare (ha) = 10,000 m², and 1 square kilometer (km²) = 100 hectares. The imperial/US customary system is less intuitive: 1 square foot = 144 square inches, 1 square yard = 9 square feet, 1 acre = 43,560 square feet, and 1 square mile = 640 acres. The key cross-system conversions are: 1 square meter = 10.764 square feet, 1 hectare = 2.471 acres, and 1 square kilometer = 0.3861 square miles.
In U.S. real estate, square footage measures interior living space, while lot size is expressed in square feet for smaller parcels and acres for larger properties. A standard suburban lot might be 7,500–15,000 square feet (roughly 0.17–0.34 acres), while rural properties are measured in acres. One acre is roughly the size of a football field without the end zones (a football field including end zones is 1.32 acres). International real estate uses square meters for interior space and hectares for land — a 150 m² apartment equals approximately 1,615 sq ft. When comparing property prices internationally, converting to a consistent unit (price per square foot or price per square meter) enables meaningful comparison.
Agriculture uses larger area units suited to field-scale operations. In the U.S., farmland is measured in acres — the average U.S. farm is approximately 445 acres. Globally, the hectare is standard — one hectare equals roughly 2.47 acres. Crop yields are reported per acre (U.S.) or per hectare (international): for example, U.S. corn averages about 175 bushels per acre, while the international equivalent would be approximately 11 tonnes per hectare. Historical land units still appear in legal documents: a section equals 640 acres (1 square mile), a quarter section equals 160 acres (the original Homestead Act allotment), and a township equals 36 sections (23,040 acres).
Construction projects require precise area calculations for material estimation. Flooring: Calculate the room's square footage (length × width), then add 10% for waste (square rooms with simple layouts) or 15–20% for waste (diagonal installations, complex room shapes, or patterned materials). Tile is typically sold by the square foot, while hardwood and laminate are sold by the carton covering a specified area (usually 20–25 sq ft per carton). Paint coverage: One gallon of interior paint covers approximately 350–400 square feet on smooth surfaces. Calculate wall area (perimeter × ceiling height) minus door and window openings. Roofing uses "squares" — one roofing square equals 100 square feet. A 2,000 sq ft roof footprint with a 6/12 pitch has approximately 2,240 sq ft of actual roof surface area (multiplied by the pitch factor of 1.12), requiring about 22.4 squares of roofing material.
Legal property descriptions in the U.S. use several systems. The metes and bounds system (common in eastern states) describes boundaries using compass bearings and distances from a starting point — calculating the enclosed area requires trigonometry or surveying software. The Public Land Survey System (PLSS) used in western states divides land into townships, sections, and fractional parts — a "quarter of a quarter section" is 40 acres. Lot and block descriptions reference recorded plat maps where each lot has a surveyed area. When purchasing land, always verify the actual surveyed area against the listed area — discrepancies of 5–10% between deed descriptions and physical surveys are common, especially with older properties.
Real-world areas are rarely perfect rectangles. For irregular shapes, several methods work: divide and conquer — break the shape into rectangles, triangles, and circles, calculate each, and sum them. Coordinate method — if you have GPS coordinates for each corner, the Shoelace formula calculates exact area from the coordinate pairs. Grid method — overlay a scaled grid and count full squares plus estimate partial squares. Modern tools simplify this: smartphone apps using GPS can walk a property perimeter and calculate the enclosed area to within 2–5% accuracy, while professional survey-grade GPS achieves sub-centimeter precision. For landscaping projects, Google Earth's measurement tool provides quick aerial area estimates sufficient for ordering materials like soil, mulch, or sod.
For everyday reference, these approximate equivalents help with quick mental estimates. A standard parking space is about 180 sq ft (roughly 17 m²). A studio apartment averages 400–600 sq ft (37–56 m²). A two-car garage is approximately 400–576 sq ft (37–54 m²). A tennis court is 2,808 sq ft (261 m²). A basketball court is 4,700 sq ft (437 m²). An Olympic swimming pool deck area is roughly 13,450 sq ft (1,250 m²). A football field (including end zones) is 57,600 sq ft (5,351 m², or 1.32 acres). These benchmarks provide intuitive scale when evaluating property listings, construction quotes, or land areas — knowing that your yard is "about half a basketball court" communicates size more effectively than abstract numbers alone. When precision matters for purchasing materials, calculating costs, or filing legal documents, always use exact measurements rather than rough benchmarks.
This converter handles all major area unit conversions instantly, saving you from manual arithmetic and ensuring accuracy across metric, imperial, and specialized measurement systems.
See also: Length Converter · Volume Converter · Weight Converter
→ Know the key real estate conversions. 1 acre = 43,560 sq ft ≈ 4,047 sq m. 1 hectare = 10,000 sq m ≈ 2.47 acres. 1 sq mile = 640 acres. These come up constantly in property listings.
→ Visualize acre size. An acre is about 90% of a football field (without end zones). A quarter-acre lot (10,890 sq ft) is a typical suburban home site — roughly 100 × 109 feet.
→ Square units don't scale linearly. Doubling a room's dimensions quadruples the area. A 12×12 room (144 sq ft) is 4× the area of a 6×6 room (36 sq ft), not 2×.
→ Use for material estimation. Once you have area in the right units, multiply by coverage rates: paint (350 sq ft/gallon), mulch (one yard covers 108 sq ft at 3"), or sod ($0.30–0.80/sq ft). See our Square Footage Calculator.
See also: Square Footage · Area Calculator · Length Converter · Acre Calculator