Square Miles to Acres converter

Convert square miles (mi²) to acres (ac) — results update instantly as you type.

Square Miles to Acres

To640

1 mi² = 640 ac

How to convert Square Miles to Acres

Area measurements describe surfaces — from apartment floor plans in square meters or square feet to farmland in acres and hectares, and entire countries in square kilometers or square miles.

Every area unit is a length unit squared, which is why conversion factors are large: one acre equals exactly 4,046.8564224 square meters and one hectare is exactly 10,000 square meters.

Formula

mi² × 640 = ac

Multiply your square miles value by 640 to get acres. For the reverse, divide by the same factor.

Square Miles to Acres conversion table

Square MilesAcres
1 mi²640 ac
2 mi²1,280 ac
5 mi²3,200 ac
10 mi²6,400 ac
25 mi²16,000 ac
100 mi²64,000 ac

Common use cases

  • Real estate listings between square feet and square meters
  • Farmland and plots between acres and hectares
  • Country and city size comparisons
  • Construction material coverage estimates

Frequently asked questions

One acre equals 43,560 square feet, or about 4,047 square meters — roughly 90% of an American football field.