About Coordinates Online

Coordinates Online provides free, privacy-focused tools for working with geographic and orbital coordinates. Whether you're converting GPS coordinates, visualizing GeoJSON data, or tracking satellites, our tools run entirely in your browser.

Our Mission

We believe geospatial tools should be accessible to everyone. Professional GIS software can be expensive and complex. Our goal is to provide simple, powerful tools that work instantly without accounts, downloads, or data uploads.

Privacy First

Your data stays on your device. All coordinate conversions, GeoJSON transformations, and calculations happen client-side in your browser. We don't collect, store, or transmit your geographic data.

The only exception is our satellite catalog, which is fetched from our database. But the orbital calculations and position predictions are performed locally.

Technology

Coordinates Online is built with modern web technologies:

  • Astro - Fast, modern static site framework
  • React - Interactive UI components
  • OpenLayers - Map visualization
  • Globe.gl - 3D satellite visualization
  • Proj4js - Coordinate transformations
  • satellite.js - SGP4 orbital propagation

Data Sources

Our satellite catalog is updated daily from official sources:

  • Space-Track.org - Official NORAD TLE data
  • CelesTrak - Aggregated orbital elements

Coordinate system definitions come from the EPSG geodetic parameter registry via epsg.io.

Open Source

The computation libraries powering this site are open source and well-tested. We believe in transparent, verifiable calculations for scientific and engineering applications.

Contact

Have feedback, questions, or suggestions? We'd love to hear from you.

Disclaimer

While we strive for accuracy, these tools are provided "as is" without warranty. For mission-critical applications, always verify calculations against authoritative sources. Satellite positions are predictions and may deviate from actual positions, especially for older TLEs or after orbital maneuvers.

Get Started

Ready to try our tools? Jump into coordinate conversion or satellite tracking.