🌎🔍 Quickly find the the nearest U.S. ZIP codes to a latitude/longitude geolocation using k-nearest neighbors

Takes a geolocation and returns the nearest US ZIP codes.

⚠️ NOTE: The top result may not return the actual ZIP code containing the location. This library returns the ZIP code where the approximate center of the ZIP is nearest the given location. Larger ZIP code areas may show lower in the results when searching nearby points because the center can be so far away. If you're relying on something as inaccurate as ZIP codes, the top result is likely close enough.

Also, ZIP codes change. They change in shape and location. New ones are created and old ones are removed. They're even recycled. If you know of a reliable, more up-to-date list of ZIP codes, please let us know by opening an issue.

Can I use this in the browser? Yes but please don't. This is made to run on a Node.js server. This depends on a roughly 2 MB list of US ZIP codes and sorts those in-memory. Please don't do that to my phone. If you're experimenting or know what you're doing, use this wherever and however it works for you.

Isn't sorting and filtering on a 2MB file slow in JavaScript? No. A lookup is created when the main file is imported/required. After the lookup is created, you should be able to run the examples in this README millions of times per second; showing output would be the limit. The tradeoff is your server may take a 1-2 seconds longer to start up initially (e.g. from npm run start).

With Yarn or npm installed, run:

yarn add geo2zip

# ...or, if using `npm`
npm install geo2zip

Get the nearest ZIP to a location:

import geo2zip from "geo2zip";

const location = {
  latitude: 34.659698,
  longitude: -88.242903,
};

const closestZip = await geo2zip(location);

console.log(closestZip); // ['38873']

Get the closest 5 ZIPs to a location:

import geo2zip from "geo2zip";

const location = {
  latitude: 34.659698,
  longitude: -88.242903,
};

await geo2zip(location, { limit: 5 });
// [ '38873', '38838', '38827', '38859', '38852' ]

Type: Object

A geolocation with valid latitude and longitude properties.

Type: Object

Properties:

• limit - the number of results to return
  • Type: Number
  • Default: 1

• standardize-geolocation - takes geolocations of different formats and outputs a standardized version
• sphere-knn - find the k nearest neighbors for points on a sphere
• us-zips - a list of US ZIP codes and their geolocations

MIT