MapTools Knowledge Base

Thirty years of teaching search-and-rescue teams and park rangers to read a map — now searchable. Ask anything.

Example — a question and its answer

“Is there a quick guide to USNG (US National Grid)?”

Yes. USNG (U.S. National Grid) is the civilian U.S. packaging of the UTM grid, used primarily by FEMA, emergency response, and some SAR teams.

A complete USNG coordinate has five parts:

10S GJ 06832 44683

10S — Grid Zone Designation (UTM zone + latitude band letter)
GJ — 100,000-meter Square ID (two letters identifying a 100km square)
06832 — Easting (east-west position within the square, in meters)
44683 — Northing (north-south position within the square, in meters)

USNG is nearly identical to MGRS; the difference is that USNG is the civilian standard for U.S. emergency response, while MGRS is military/NATO. They use the same map grid and five-component structure.

When writing or speaking USNG, use spaces between the parts. If everyone is in the same 100km square, you can drop the zone and square ID and just use the easting and northing — but that's risky at boundaries.