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Conversion Formula:
Convert Acre to Tatami Mat (ac to tatami) 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.
Acre (ac) - Imperial/US land area
Acre is a traditional unit of area used for land measurement in the UK, US, and other countries. Used in real estate, agriculture, and land records; metrically it converts exactly because the foot is defined in meters.
- Symbol: ac
- System: Imperial/US customary (non-SI, accepted for use with SI
- Exact relations: 1 acre = 43,560 ft² = 4,840 yd² = 160 square rods (perches/poles) = 10 square chains
- Metric equivalents (exact): 1 acre = 4046.8564224 m² ≈ 0.40468564224 ha
- Typical examples: suburban lots (fractions of an acre); farm fields of tens to hundreds of acres; sports complexes measured in multiple acres
Tatami mat (畳, jō) - Japanese flooring unit of area
Tatami mat is a traditional Japanese flooring module used as a practical unit of area; room sizes are often stated by the count of mats (jō). Dimensions vary regionally, so one tatami has no single national standard.
- Names/aliases: tatami, 畳 (jō); room size written as “n-jō”
- System: Traditional Japanese (non-SI)
- Typical sizes (area):
• Kyōma (Kyoto): 0.955 m × 1.910 m = 1.824 m² ≈ 19.63 ft²
• Chūkyōma (Nagoya): 0.910 m × 1.820 m = 1.656 m² ≈ 17.83 ft²
• Edoma/Kantōma (Tokyo area): 0.880 m × 1.760 m = 1.5488 m² ≈ 16.67 ft²
• Other regional modules exist; common range ≈ 1.55–1.82 m² per mat
- Room estimates: 6-jō room ≈ 9–11 m² depending on region; 8-jō ≈ 12–15 m²
- Construction note: buildings often use tatami modules as planning grids; mats are rectangular with length ≈ 2 × width