ZIP code map
Boundaries are Census ZIP Code Tabulation Areas (2020). A ZIP code is a set of mail routes rather than an area, so these shapes approximate them — they are the closest official thing to a ZIP code boundary that exists.
Using the map
Zoom in to see individual ZIP code areas; below the level of a whole region the country is drawn as one shape, and above street level the 2020 boundary would claim more precision than a ZIP code has. Click any area to open its page: the town the Postal Service addresses it as, its county split, Census figures for the people living there, and the nearest ZIP codes by distance.
What is not on it
About 7,900 ZIP codes have no area at all: PO-box-only codes, codes for a single company or government building, and military mail. They are mail routes without residents, so the Census draws no shape for them. They still have pages, with the post office's location instead of a boundary.