DMS to Decimal Degrees Converter
Convert Degrees, Minutes, and Seconds to Decimal format. Crucial for digitizing historic deed descriptions and survey records.
Quick Reference
DMS Formula: Decimal = Degrees + (Minutes ÷ 60) + (Seconds ÷ 3600)
Example: 40°26'47"N = 40 + (26/60) + (47/3600) = 40.446944°N
💡 Pro Tip: Always verify hemisphere direction (N/S, E/W)—sign errors cause 180° positional mistakes.
DMS to Decimal Degrees — Conversion Table
Common DMS values and their decimal equivalents. Use this table for quick reference or verify your conversion results.
| DMS Input | Decimal Degrees | Description |
|---|---|---|
| 0° 0' 1" | 0.000278° | One arc-second (~31 meters at equator) |
| 0° 1' 0" | 0.016667° | One arc-minute (~1.85 km at equator) |
| 0° 30' 0" | 0.500000° | Half a degree (~55.5 km at equator) |
| 1° 0' 0" | 1.000000° | One degree (~111 km at equator) |
| 33° 51' 54" | 33.865000° | Los Angeles, CA (latitude) |
| 35° 41' 22.4" | 35.689556° | Tokyo, Japan (latitude) |
| 40° 44' 55.7" | 40.748806° | Empire State Building, NYC (latitude) |
| 48° 51' 24" | 48.856667° | Eiffel Tower, Paris (latitude) |
| 51° 28' 38" | 51.477222° | Greenwich Observatory, London (latitude) |
| 90° 0' 0" | 90.000000° | North Pole |
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よくあるご質問 (FAQ)
What is DMS format and why is it used?
DMS (度・分・秒) is the traditional format for expressing coordinates, inherited from maritime navigation. 1 degree = 60 minutes; 1 minute = 60 seconds. Professional surveyors and historical deed descriptions use DMS because it's human-readable and represents historical measurements from surveying instruments (theodolites, transits).
How many decimal places do I need for accuracy?
6 decimal places: 0.11m precision (professional standard). 5 decimal places: 1.1m precision (acceptable for GIS). 4 decimal places: 11m precision (land survey only with caution). Less than 4: Not acceptable for professional use.
What does N/S and E/W mean, and why is it critical?
N = North (positive latitude), S = South (negative). E = East (positive longitude), W = West (negative). Misinterpreting hemisphere causes a sign flip, placing coordinates 180° away. A fence built using the wrong hemisphere notation could end up on the opposite side of the Earth.
DDM vs DMS—what's the difference?
DDM (Decimal Degrees Minutes) is 40°26.7867', while DMS is 40°26'47.04". DDM is a hybrid format used by some GPS receivers. This tool converts DMS to pure decimal degrees (DD), the standard for GIS and professional mapping systems.
The $50,000 Geodetic Drift Liability: NAD83 vs WGS84
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。