legal unit of measurement
1 square kilometer (km) = 100 hectares (hm) = 247.1 acres (acre) = 0.386 square miles (mile)
1 square meter (m) = 10.764 square feet (ft) 1 acre (are) = 100 square meters (m)
1 hectare (hm) = 15 acres = 1hm2 = 10,000 square meters (m) = 2.471 acres (acre) = 0.01 square kilometers (where h means one hundred meters, and hm2 means one hundred meters squared)
1 square mile (mile) = 2.590 square kilometers (km)
1 acre (acre) = 0.4047 hectare (ha) = 4.047 × 10 square kilometers (km) = 4047 square meters (m)
1 square foot (ft) = 0.093 square meters (m) 1 square inch (in) = 6.452 square centimeters (cm)
1 square yard (yd) = 0.8361 square meters (m)
1 mu=2000/3 square meters≈666.666 square meters
Municipal measurement unit
1 square mile = 22,500 square feet
1 square foot = 100 square feet
1 square foot = 100 square inches
1 square inch = 100 square minutes
1 square minute = 100 square centimeters
1 square centimeter = 100 square millimeters