A national map with no tile server

32,000 ZIP-code areas is far past what a GeoJSON source can carry. This map streams geometry from a PMTiles archive — one static file, fetched in ranged slices as you pan — and joins a small JSON of values in the browser. Switching measures repaints without touching the geometry again.

CDC PLACES · ZIP-level model estimates

Obesity prevalence, every ZIP code at once

Percent of adults with BMI ≥ 30. Zoom in — the geometry streams by viewport from a single static file, so the whole country costs a few hundred kilobytes, not the 39 MB the archive holds.

28.034.040.0

lowerhigher (%)

Not estimated

CDC PLACES ZIP-level model-based estimates via ontopic-public-data; ZCTA geometry tiled with tippecanoe, served as PMTiles from object storage.

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