Convert Square Nautical Miles to Square Chains
Convert Square Nautical Miles (nmi²) to Square Chains (ch²) instantly and accurately.
Conversion Formula
ch² = nmi² × 8475.477363
About Square Nautical Miles
A square nautical mile (nmi²) equals the area of a square with sides of one nautical mile (1,852 m), giving approximately 3,429,904 m² - about 343 hectares. This unit is used in maritime and aviation contexts to describe patrol zones, territorial extents, and maritime boundaries. Exclusive Economic Zones (EEZs) and military operating areas are often quoted in square nautical miles. One square nautical mile is approximately 1.32 square statute miles.
About Square Chains
A square chain (ch²) is a surveying unit equal to the area of a square with sides of one Gunter's chain (66 feet or ~20.12 m), approximately 404.69 m². Ten square chains equal exactly one acre, making it the natural subdivision unit in traditional land surveying. The US Public Land Survey System used chains to lay out townships and sections, and square chains appear throughout old legal property descriptions and government land grants across North America. One square chain equals exactly 16 square rods.
Quick Reference Table
| Square Nautical Miles (nmi²) | Square Chains (ch²) |
|---|---|
| 1 nmi² | 8475.48 ch² |
| 2 nmi² | 16951 ch² |
| 5 nmi² | 42377.4 ch² |
| 10 nmi² | 84754.8 ch² |
| 25 nmi² | 211887 ch² |
| 50 nmi² | 423774 ch² |
| 100 nmi² | 847548 ch² |