Convert local XYZ tile pyramids (z/x/y directories) to Cloud Optimized GeoTIFF. All processing happens in your browser—nothing is uploaded.
Web Worker decodes tiles in the background
Tile data never leaves your browser
Output follows the Cloud Optimized GeoTIFF spec
Select a local XYZ tile directory (structure: z/x/y.png)
XYZ Tiles to COG TIFF makes the reverse trip: point it at a local z/x/y tile directory and it merges the pyramid back into a single Cloud Optimized GeoTIFF. It detects the zoom levels and tile counts in the folder automatically, decodes PNG, JPEG, and WEBP tiles in a background worker, and writes a COG with internal overviews - compressed with DEFLATE or LZW plus an optional predictor you control.
It turns cached or downloaded tile sets back into analysis-ready raster data: recover an archived map service as one georeferenced image, or hand a tile-based basemap over to desktop GIS software that expects a GDAL-readable file.
Select the tile directory with read-write access - the z levels found in the folder and the total tile count are detected and reported before conversion.
Pick the compression (DEFLATE, LZW, or none) and the predictor; horizontal differencing is the recommended setting and usually shrinks the file further.
Run the conversion; the resulting output.tif is written straight into the tile folder you selected, so there is no separate download step.
AA Cloud Optimized GeoTIFF is internally tiled and carries pyramid overviews, so readers can stream just the portion they need over HTTP. TiTiler, QGIS, and most cloud geospatial platforms open COGs remotely without downloading the whole file first.
AThe highest zoom level in the directory provides the base resolution, while the lower levels are embedded as overviews for fast rendering at small scales. A level-z pyramid contains on the order of 2^z squared tiles of ground detail, so keep the cached range reasonable in both directions.
APNG, JPG/JPEG, and WEBP tiles arranged in the standard z/x/y directory layout. All decoding happens locally in the browser worker - the tiles are never uploaded anywhere.