How to Upload and Analyze Your Own GeoTIFF in the Browser

Why Upload Your Own Data?

Satellite imagery from Sentinel-1 and Sentinel-2 covers the globe, but many analysis workflows involve custom datasets:

• Derived products — NDVI composites, classification maps, or DEM data processed in other tools
• Historical archives — Older satellite data not available through standard STAC APIs
• Drone imagery — High-resolution orthomosaics from UAV surveys
• Model outputs — Flood models, land use predictions, or climate projections in raster format

Being able to overlay these custom datasets with live satellite imagery — without leaving the browser — eliminates the constant switching between tools that slows down analysis.

Supported Formats

The Data Loader accepts:

Format	Extension	Notes
GeoTIFF	.tif, .tiff	Standard georeferenced raster
Cloud-Optimized GeoTIFF (COG)	.tif	Preferred for large files — supports partial loading
GeoJSON	.geojson, .json	Vector boundaries and features

For raster data, Cloud-Optimized GeoTIFF is recommended for files larger than ~50MB, as it supports progressive loading without downloading the entire file.

Step-by-Step: Uploading a GeoTIFF

1. Prepare Your File

Ensure your GeoTIFF has:

• A coordinate reference system (CRS) — EPSG:4326 (WGS 84) or EPSG:3857 (Web Mercator) work best. Most CRS are supported and will be reprojected automatically.
• Valid data range — Know the expected min/max values for proper visualization

2. Open the Data Loader

Navigate to the Data Loader from the sidebar or main menu. You'll see a drag-and-drop zone.

3. Upload Your File

Drag your GeoTIFF file onto the upload zone, or click to browse. The file is processed entirely in your browser — nothing is uploaded to a server.

4. Adjust Visualization

Once loaded, your data appears on the map. You can:

• Adjust min/max values to optimize contrast for your data range
• Apply colormaps (grayscale, viridis, plasma, inferno, etc.)
• Set opacity to see satellite imagery beneath your overlay

5. Combine with Satellite Data

With your GeoTIFF loaded, search for satellite imagery over the same area. Both layers will appear in the layer manager, where you can:

• Toggle visibility
• Adjust layer order
• Compare your data against the satellite background

Practical Use Cases

Overlay a DEM with Optical Imagery

Upload a digital elevation model to understand topographic context when interpreting satellite imagery. Mountains, valleys, and slope aspects significantly affect what you see in both optical and SAR imagery.

Compare Your Classification with Source Data

Upload a land use classification map and overlay it with the Sentinel-2 imagery it was derived from. This visual comparison helps identify misclassification areas that need refinement.

Validate Flood Models

Upload a flood model's predicted inundation extent and compare it against actual SAR-based flood observations. The difference between predicted and observed flooding reveals model accuracy.

View Historical Imagery

Upload archived satellite imagery (Landsat, SPOT, etc.) and compare it with current Sentinel-2 data to analyze long-term land use change.

Tips for Best Results

File Size Considerations

• Files under 100MB load quickly in most browsers
• For larger files, convert to Cloud-Optimized GeoTIFF first — this allows the browser to load only the portion visible at your current zoom level
• Single-band files are faster to load than multi-band files

Coordinate System

If your file uses a local or uncommon CRS, it will be reprojected on the fly. For fastest performance, pre-convert to EPSG:4326 or EPSG:3857.

NoData Values

Ensure your GeoTIFF has proper NoData values set for areas without data. This prevents black borders or zero-value artifacts when overlaying with other data.

Multi-Band Files

For multi-band GeoTIFFs, the Data Loader will display the first band by default. You can select different bands or band combinations depending on your data.

Privacy and Security

Your uploaded data never leaves your browser. The Data Loader uses client-side JavaScript to read and render the GeoTIFF — no server upload occurs. This means:

• No data transfer — Your proprietary data stays on your machine
• No storage costs — Nothing is stored on our servers
• No size limits from server upload — Limited only by your browser's memory

Try It Now

1. Go to the Data Loader
2. Upload any GeoTIFF file you have
3. Adjust the visualization parameters
4. Search for satellite imagery over the same area to create a composite view

If you don't have a GeoTIFF handy, try downloading a free DEM tile from OpenTopography or a Landsat scene from USGS EarthExplorer.