Coordinate Converter

Coordinate Converter: Core Features and Principles

When WGS84 coordinates obtained by GPS devices show offsets on Chinese maps, this tool uses professional algorithms to achieve high-precision conversions between different coordinate systems. The coordinate converter processes geolocation data (latitude/longitude coordinates or text addresses) and outputs coordinates in the target system or performs reverse geocoding. Its core capabilities include: converting location coordinates of any point on the Earth's surface (represented in degrees, minutes, seconds or decimal degrees) between the three major coordinate systems: WGS84 (international standard), GCJ02 (China official encrypted), and BD09 (Baidu encrypted), as well as supporting geocoding and reverse geocoding.

Why Choose Our Coordinate Converter?

• Supports Three-System Conversion: Covers conversions between WGS84, GCJ02, and BD09 coordinate systems, solving the core pain point of map offsets in China.
• Dual Format Compatibility: Processes both Degrees, Minutes, Seconds (DMS) and Decimal Degrees (DD) coordinate inputs, adapting to the output formats of different devices.
• Meter-Level Accuracy Guarantee: Uses the official offset algorithm, controlling positioning accuracy within a 1-3 meter range.

Tool Tutorial

1. Select Conversion Type: Click the "Coordinates to Address", "Coordinate System Conversion", or "Address to Coordinates" tabs.
2. Input Raw Data: Paste the coordinates (e.g., 39.9087, 116.3974) or a detailed address into the text box.
3. Set Conversion Parameters: For coordinate system conversion, select the source coordinate system (e.g., WGS84) and the target coordinate system (e.g., GCJ02).
4. Get Results: The converted coordinates are output in decimal format, and the geocoding results include four-level administrative information: province, city, district, and street.

Frequently Asked Questions (FAQ)

Q: Why do mobile GPS coordinates show deviations on Amap (Gaode)?
A: The direct cause is a coordinate system mismatch. Mobile GPS uses WGS84 coordinates, while Amap uses the GCJ02 coordinate system. You need to convert them using this tool.

Q: What is the accuracy difference range when converting between BD09 and GCJ02?
A: The Baidu coordinate system (BD09) is encrypted a second time based on GCJ02, and the conversion error is usually ≤ 1 meter. However, in remote areas, due to different encryption parameters, the maximum error may reach 3-5 meters.

Important Notes

• Geocoding requires complete administrative division information (e.g., "No. 27 Zhongguancun Street, Haidian District, Beijing").
• Coordinate system conversion does not apply to elevation data; it only processes planar coordinates.
• Please do not upload sensitive location coordinates. Our service does not save user data.
• The maximum limit for a single processing is 50 entries. Batch file conversion is not supported.

Professional Technical Notes & Usage Suggestions

When developing GIS systems, it is recommended to unify the base coordinate system first. For example, convert WGS84 coordinates collected by drones to GCJ02 before integrating them into the Amap API. A typical conversion example: WGS84 coordinates (116.397456, 39.907761) → GCJ02 coordinates (116.403119, 39.914525). The offset is about 700 meters, which matches the encryption parameter characteristics of the Beijing area.