Easily convert latitude and longitude coordinates to Military Grid Reference System (MGRS) format. This tool
provides a simple interface for quick and accurate conversions, essential for military, navigation, and outdoor
activities.
MGRS is used in tactical mapping, SAR, and military navigation because it provides concise grid references. Converting to MGRS ensures compatibility with field reports and rescue teams that require standardized grid coordinates.
What causes a 100km grid error?
Grid letter mistakes happen when the wrong 100km square is selected. A single wrong pair of letters can place your point in a completely different search block, which is why validation at the moment of conversion is critical.
How precise is 10-digit MGRS?
A 10-digit MGRS string provides approximately 1-meter precision. If you need better than 1m accuracy, use survey-grade GNSS solutions or professional geodetic control because the grid itself is not designed for sub-meter specification.
Can I use this for aerial imagery?
Yes, but only if your imagery is referenced to WGS84 and the coordinate precision meets the required survey standard. Always verify the datum and zoning before overlaying MGRS on aerial or drone imagery.
使い方
Enter your latitude and longitude values in the respective fields. Ensure usage of decimal degrees. Click the
'Convert' button to generate the MGRS coordinate. The result will appear instantly below the button.
A: はい。WGS84楕円体準拠の標準MGRSアルゴリズムに基づき、10桁MGRS（1m解像度）までミリ秒単位で正確に計算します。ただし重要インフラ工事等では必ず現地基準点との照合を行ってください。
coordinates with multiple sources if safety is at risk.
This content is provided for decision-support and educational purposes for geospatial professionals and does not
constitute legal, surveying, or engineering advice.
Regulations and official standards vary by jurisdiction and project scope. Information is based on publicly
available standards as of January 11, 2026.
For critical projects, always verify current requirements with:
Licensed Professional Surveyors or Professional Engineers
(PE) in the relevant jurisdiction
Certified attorneys for legal interpretation of regulations
Current guidelines from relevant
authorities (FAA, JCAB, GSI, etc.)
The 1-2 Meter (3-6 Foot) NAD83 Shift: Because the North American Plate drifts, WGS84 and NAD83(2011) are currently out of sync by up to 2 meters in the conterminous US. Mixing these datums in construction or boundary litigation introduces errors that exceed legal and engineering tolerances. Understand the precise offset mechanics.
What is the MGRS precision level equivalent to distance?
MGRS precision depends on the digits after the 100km identifier: 10-digit (1 meter), 8-digit (10 meters), 6-digit (100 meters), and 4-digit (1,000 meters). True positional accuracy depends entirely on your initial GPS geometry collection.
Is UTM or State Plane Coordinate System (SPCS) more accurate?
Neither system is inherently more accurate mathematically; both are conformal map projections. The difference is their engineered linear scale distortion. UTM uses global 6-degree zones with scale factors ranging from 0.9996 at the central meridian to ~1.0010 at zone edges (varying by up to 1:1,000 to 1:2,500). SPCS divides individual US states into narrower zones designed so projection scale distortion on the ellipsoid does not exceed 1 part in 10,000 (0.01%) across the zone. For high-precision cadastral and construction layout, SPCS minimizes projection scale error, though surveyors must also apply elevation factors to compute ground distances.
A single 100km grid letter error (e.g., "PV" vs "QV") has historically displaced 検索 and Rescue (SAR) teams by exactly 100km, with documented fatalities in high-stakes terrain. NATO STANAG 2029 operations mandate 10-digit MGRS for tactical coordination; truncating to 4 digits expands the uncertainty radius from 1m to 1km.