Area Converter

Recognize squared units

Square meters (m²) and square feet (ft²) measure area, rather than a length or volume. The length factor applies twice: 1 ft² = (0.3048 m)² = 0.09290304 m². Metric prefixes also square: 1 km² = (1000 m)² = 1000000 m².

• Convert length dimensions

Convert a stated area

If the source already gives an area, select its area unit directly. Multiply square feet by 0.09290304 to obtain square meters, or divide square meters by that factor to obtain international square feet. Calculate using the definitions and round the final display, rather than using a rounded reciprocal as a new exact factor.

• Square feet to square meters
• Square meters to square feet

Calculate a rectangle from its dimensions

For a hypothetical rectangle measuring 10 ft × 12 ft, both dimensions are in the same length unit: 10 × 12 = 120 ft². Convert the area: 120 × 0.09290304 = 11.1483648 m² before rounding. Alternatively, (10 × 0.3048 m) × (12 × 0.3048 m) gives the same result.

Do not multiply one dimension in feet by another in meters and label the result m². Irregular shapes require their own geometry and measurements; a unit conversion alone cannot find their area.

• Compare construction quantities

Identify the land-unit definition

NIST lists the hectare as a non-SI unit accepted for use with the SI, equal to 10000 m². Its revised land-unit table defines the international-foot acre as 43560 ft² = 4046.8564224 m², and a square mile as 640 acres.

From those definitions, 100 acres = 100 × 4046.8564224 / 10000 = 40.468564224 ha. The reciprocal is 10000 / 4046.8564224 acres per hectare; 2.47105 is only a rounded display factor.

Historic surveys may specify U.S. survey feet. NIST distinguishes that definition from the international foot. Check the actual source unit; these international-foot factors do not convert survey-foot acreage or determine legal property boundaries.

• Read the acres and hectares guide
• Acres to hectares
• Hectares to acres
• Compare stated property areas

Preserve the stated measurement precision

The unit definitions are exact, but a measured room or reported land area may be rounded or uncertain. Displaying more decimal places does not make that measurement more accurate. Keep the original quantity and convention, calculate before rounding, and select a display precision appropriate to the source.

The calculator displays 120 ft² as 11.1484 m² at its default four decimal places. At eight decimal places it displays 11.1483648 m²; these are the same conversion with different display rounding.

• Calculation methodology

Sources and review

• NIST: exact international-foot acre, foot and square-mile definitions
• NIST SP 811 Chapter 5: hectare and its non-SI status
• NIST SP 811 Appendix B.8: length and squared-unit factors
• BIPM: metric prefix multipliers (squared for area)

Reviewed 2026-10-06. Calculated values are displayed to at most ten significant digits; extra digits do not establish measurement accuracy.