Convert Chain (ch) to Megameter (Mm) instantly.
About these units
Chain (ch)
A chain is equal to 66 feet or 4 rods, and it was standardized by surveyor Edmund Gunter in the 17th century. "Gunter's chain," consisting of 100 metal links, became the backbone of land surveying in the English-speaking world for centuries. Its convenience stems from simple arithmetic: 10 square chains make an acre, making land area calculations straightforward. Railroads, farmland, and city parcels across the United States and the Commonwealth nations were once laid out using chains, so the unit appears in countless historical records. Even today, some legal property descriptions still reference chain-based measurements, making the unit relevant for modern surveyors who interpret old maps. Although high-precision digital equipment has replaced physical chains, the unit's structural role in land division ensures its lasting importance.
Megameter (Mm)
The megameter, measuring one million meters (1,000 kilometers), is useful for describing large geographical or geophysical distances on planetary scales. Earth's radius (approximately 6.37 Mm) and the thickness of atmospheric layers can be expressed effectively in megameters. This unit provides a clean and compact way to represent massive distances without resorting to scientific notation. The megameter also appears in discussions of communication signals, satellite orbits, and especially planetary science. While kilometers are still more common in public-facing contexts, megameters offer a more mathematically elegant representation for large calculations. They provide a middle ground between human-scale geography and astronomical units.