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Conversion Formula:
Convert Rood to Square Millimeter (ro to mm²) instantly with accurate, readable results.
Convert between square meters, acres, square feet, hectares, and other common units with our Area Unit Converter. This intuitive unit conversion tool helps you calculate land size, floor space, and surface area across both metric and imperial systems. Whether you're working on real estate, construction, or geography tasks, our area unit conversion calculator ensures precise and instant results.
Rood (rood) - traditional land area
Rood is a historical Imperial/US customary unit of area equal to one quarter of an acre. Used in older land records, field measurements, and some property descriptions.
- Symbol: none standardized (written as “rood”)
- System: Imperial/US customary (historic)
- Exact relations: 1 rood = 1/4 acre = 40 square rods (perches) = 2.5 square chains
- Other relations: 1 rood = 1 furlong × 1 rod = 10,890 ft² = 1,210 yd²
- Metric equivalents (exact): 1 rood = 1011.7141056 m²
- Typical examples: historical parcel sizes in deeds; subdivision remnants expressed as roods and perches
Square millimeter (mm²) - tiny metric area
Square millimeter is a metric unit of area equal to the area of a square with sides of 1 millimeter. Used for tiny surface areas, cross-sections, and component footprints in engineering and electronics.
- Symbol: mm²
- System: SI derived unit
- Exact relations: 1 mm² = (0.001 m)² = 1×10⁻⁶ m² = 0.01 cm²; 100 mm² = 1 cm²
- Imperial/US equivalents: 1 mm² = 1/645.16 in² ≈ 0.0015500031 in² ≈ 0.00001076391 ft² ≈ 0.00000119599 yd²
- Typical examples: wire cross-sectional areas (e.g., 2.5 mm²), microchip die areas, small nozzle or orifice openings