About OpenZenith
A free, open-source geospatial platform providing global elevation data, interactive maps, and geospatial APIs — powered by NASA SRTM 30m data and served on Cloudflare's global edge network.
Mission
OpenZenith exists to make elevation and geospatial data accessible to everyone. No API keys, no rate limits on basic queries, no paywalls. Whether you're building a hiking app, researching terrain, or just curious about the elevation where you stand — the data is free and fast.
What We Offer
Elevation API
Single-point and batch elevation queries. Bilinear interpolation for smooth results from NASA SRTM 30m DEM tiles.
Interactive Map
Full-featured map with multiple basemaps, hillshade layer, 3D terrain, pins with elevation data, and shareable URLs.
Globe (3D Globe)
CesiumJS-powered 3D globe with real-time data overlays: earthquakes, flights, satellites, natural events, and weather.
Data Explorer
Multi-tab data explorer with NOAA, USGS, Celestrak, OpenSky, ArcGIS, Overpass/OSM, and marine weather integrations.
Technology
The platform is built with modern, lightweight tools:
Data Sources
Elevation data comes from NASA's Shuttle Radar Topography Mission (SRTM) at 30-meter resolution, hosted as OZT-compressed tiles on HuggingFace and served via the edge runtime. Additional real-time data is proxied from:
USGS Earthquakes
Real-time and historical earthquake feeds with magnitude, depth, and GeoJSON geometry.
OpenSky Network
Real-time ADS-B flight tracking with position, altitude, speed, and callsign data.
Celestrak
Satellite TLE data for active, visual, communication, navigation, and weather satellites.
NASA EONET
Natural event tracking: wildfires, volcanoes, icebergs, landslides, and severe storms.
NWS / NOAA
Weather warnings, forecasts, and marine conditions via the National Weather Service.
Open-Meteo
Marine weather API: wave height, direction, period, wind speed, and temperature.
Author & Team
aliasfoxkde
Creator & maintainer of OpenZenith. Full-stack developer with a passion for geospatial data, open-source software, and making elevation data freely accessible.
Project History
SRTM Data Processing
Converted NASA SRTM HGT files into OZT-compressed terrain tiles, hosted on HuggingFace and optimized for edge delivery.
API Launch
Built the elevation API on Cloudflare Edge Runtime with bilinear interpolation, tile caching, and CORS-free access.
Interactive Map
Added a full-featured MapLibre GL map with hillshade, 3D terrain, multiple basemaps, and elevation pin queries.
Globe
Integrated CesiumJS for a 3D globe with real-time overlays: earthquakes, flights, satellites, and natural events.
Data Explorer
Built a multi-tab data explorer integrating NOAA, USGS, Celestrak, OpenSky, ArcGIS, and Overpass API.
Platform Expansion
Expanded with shared components, quality infrastructure (ESLint, Prettier, Vitest), and comprehensive API documentation.
Get Involved
OpenZenith is open source under the MIT license. Contributions are welcome — whether it's new data sources, bug fixes, feature requests, or documentation improvements. Visit the Contribute page to learn how to submit data or open a pull request.
License
This project is licensed under the MIT License. Elevation data is sourced from NASA SRTM, which is public domain.