用途に応じた適切な座標系の選び方ガイド
Choosing the wrong coordinate system can lead to misalignment and data failure. Follow this guide to find the system that fits your operational needs.
使い方
Follow the decision tree below to find the right tool for your project.
オンラインツール
ユースケース
- Navigating from global data (Lat/Lon) to local grid (UTM).
- Selecting the correct datum for Japanese legacy projects.
FAQ
Q: Is MGRS better for disaster response?
A: Yes, it is the standard for NATO and search-and-rescue teams due to its ease of communication and avoidance of longitude/latitude confusion over radio.
Q: When should I use UTM?
A: Use UTM for high-precision local mapping and engineering projects where metric measurements (meters) are required instead of degrees.
Q: Degrees vs Meters?
A: Use Degrees (Decimal or DMS) for global positioning and GPS logging; use Meters (UTM) for calculating distances and areas within a local zone.
Professional Verification Disclaimer
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.)
Reference: Professional Use & Scope
Related Coordinate Conversion ツール一覧
米国平面直角座標系（SPCS）変換 & ガイド
各州固有の正角投影グリッドからGPS WGS84への高精度測量・工学座標変換。
座標系選択 FAQ
What happens if I use the wrong datum? ▼
Using the wrong datum (e.g., assuming NAD27 is WGS84) causes coordinate shifts ranging from tens to hundreds of meters depending on your location. In engineering and surveying, this can lead to devastating consequences such as building across property lines, utility strikes, and massive legal liability.
Explore Technical DetailsIs UTM the same as WGS84? ▼
No. WGS84 is a global geodetic datum (an ellipsoid model of the Earth), whereas UTM (ユニバーサル横メルカトル図法) is a map projection that splits the Earth into 60 zones to create a flat 2D grid. UTM coordinates are derived from a specific datum, most commonly WGS84 or NAD83.
Explore Technical DetailsWhy do surveyors use State Plane instead of WGS84? ▼
State Plane Coordinate Systems (SPCS) are localized grid projections designed to minimize scale distortion. While WGS84 is excellent for global satellite navigation (GNSS), State Plane allows surveyors to use simple 2D Cartesian math for precise engineering design and land boundary layout with distortions typically less than 1 part in 10,000.
Explore Technical Details地殻変動と再施工リスク：NAD83 vs WGS84の累積誤差
北米プレートは年間約2cm移動するため、NAD83(2011)とWGS84(G1762)は現在2.2メートル以上乖離しています。 高精度なNAD83地籍杭打ちに「標準的な」GPS WGS84座標を使用したことで、基礎のやり直しやインフラの配置ミスによる5万ドルの専門家責任賠償請求が発生しています。