A small library for checking if a US 5 Digit ZIP code is real
npm install is-valid-us-zipA "small" library for checking if a US 5 Digit ZIP code is real.
```
npm install is-valid-us-zip
`js
const isValidUSZip = require('is-valid-us-zip');
isValidUSZip("75000") // false
`
The function will return false for a value that is not a stirng. As you can't reference some zip codes as a number, due to the starting with a 0.
Download a copy of the AREADIST_ZIP5.TXT file from USPS and pipe it into the tree builder script.
```
$ cat AREADIST_ZIP5.TXT | node build/make-tree.js
- https://postalpro.usps.com/address-quality/ais-viewer - AREADIST_ZIP5.TXT