zip codes

A black and white dot map of all the centers of ZIP codes in the continental United States.

ZIP Codes in the United States

Caitlin Dempsey

It’s likely that if you routinely send mail to a location within the United States, you know how critical it ...

A black and white dot map showing ZIP codes in the continental United States.

Understanding and mapping ZIP Codes

Caitlin Dempsey

Resources for accessing ZIP code data. Ben Fry has created zipdecode that shows the location of all the ZIP codes in the United States.

ZIP Code boundaries overlayed with the City of Flint's boundary. Map: Richard Casey Sadler.

How the ‘Quirky Geography’ of ZIP Codes Obscured Flint’s Lead Problem

Caitlin Dempsey

Richard Casey Sadler, an assistant professor at Michigan State University discusses how the Michigan Department of Health and Human Services' reliance on using ZIP Code level data obscured the link between Flint residents and lead exposure.

ZIP Code Data is “Commercially Sensitive” Per the US Postal Service

Caitlin Dempsey

Robb Shecter of the Weblaws.org site wanted to map out restaurant health inspections in Multnomah County, Oregon as part of his ...