Quick Reference
UTM Format: Zone + Letter + Easting + Northing (e.g., 51S 377561 4621522)
Example: 40.7128°N, -74.0060°W = 18T 584384 4509355
💡 Pro Tip: Each UTM zone is 6° wide. Crossing zone boundaries without recomputing causes 554km errors in autonomous systems.
UTM Zone Reference Table — Major Cities
Quick reference for which UTM zone covers major world cities:
| City | Lat/Long | UTM Zone | UTM Coordinates |
|---|---|---|---|
| New York, USA | 40.7128°N, 74.0060°W | 18T | 583960 E, 4507523 N |
| London, UK | 51.5074°N, 0.1278°W | 30U | 699311 E, 5710164 N |
| Tokyo, Japan | 35.6762°N, 139.6503°E | 54S | 371276 E, 3949459 N |
| Sydney, Australia | 33.8688°S, 151.2093°E | 56H | 334786 E, 6251930 N |
| Paris, France | 48.8566°N, 2.3522°E | 31U | 448251 E, 5411935 N |
| São Paulo, Brazil | 23.5505°S, 46.6333°W | 23K | 332784 E, 7394372 N |
よくあるご質問 (FAQ)
What is UTM and why use it instead of lat/long?
UTM (ユニバーサル横メルカトル図法) divides Earth into 60 zones, each 6° wide, with a uniform scale factor. Unlike lat/long, UTM coordinates are in meters, making distance calculations and GIS analysis simpler. UTM is the standard for engineering, construction, and many government agencies (USGS, FEMA, military).
What is the UTM zone letter and why does it matter?
The letter indicates latitude bands (C–X, excluding I and O). The zone number indicates longitude (1–60, starting from 180°W). Both zone and letter are critical—using the wrong combination places your coordinates thousands of kilometers away.
What causes the 554km "robot snap" error?
When a vehicle or robot crosses a UTM zone boundary, its x/y coordinates jump dramatically (because each zone has its own easting origin). If the system doesn't recompute the UTM zone, the robot perceives itself 554km away. This caused an autonomous lawnmower to fail mid-operation.
What is the UTM scale factor (0.9996) and how does elevation affect it?
UTM uses a scale factor of 0.9996 at the central meridian of each zone to minimize distortion. At zone edges, distortion reaches ±0.04%. At high elevation (e.g., 1000m above sea level), the effective scale factor drifts, causing 15cm/km errors in mountainous terrain. SAR (検索 and Rescue) operations must account for this.
Precision Penalty: Scale Factor Distortion & SPCS Liability
In mountainous US SPCS zones (e.g., Colorado, California), combined scale factor errors reach 15cm per kilometer. Treating grid coordinates as ground distances without applying (Grid x Elevation) corrections has voided construction contracts and caused catastrophic pipeline strikes by misinterpreted offset stakes.