area · Survey / land measure · Historical-modern

square chain

exact

Definition

One square chain is 4,356 square feet = exactly 404.68564224 m² using the modern foot.

One square chain is exactly 404.68564224 square metres.

Traditional acre arithmetic is built around chains and rods rather than arbitrary-looking square-foot numbers.

Modern use is context-dependent and varies by region or measurement system.

Source tier — · confidence high

area · International · Modern

Non-SI unit accepted for use with the SI; 1 ha = 10⁴ m².

m²

area · International · Modern

Coherent SI derived unit for area, equal to metre squared.

area · UK / US · Modern / historical

1 acre = 43,560 ft² = exactly 4046.8564224 m² using the international foot.

ft²

area · UK / US · Modern / historical

1 ft² = exactly 0.09290304 m².

yd²

area · UK / US · Modern / historical

1 yd² = exactly 0.83612736 m².

mi²

area · UK / US · Modern / historical

1 mi² = exactly 2,589,988.110336 m².

km²

area · International · Modern

1 km² = exactly 10^6 m².

in²

area · US / UK · Modern

1 in² = exactly 0.00064516 m².