Area codes and zip codes--you often need them and rarely have them. Although you can't mail anything without a zip code, people often exclude it when they hastily jot down or leave their street address. If you live in a state with overlaying area codes, call another state, or need to call information in another state, you must dial those three extra numbers. Where can you find the zip code for Acmar, Alabama or the area code for Idman, Idaho? Try the following sites.

United States Postal Service
Where better to get a zip code than the United States Postal Service? They deliver the mail, after all. You can type in a residential or business address, and USPS will give you the zip code. Although you can search for zip codes by city, searching by street address is more efficient because many cities have more than one zip code. If you need the name of a city or cities within a certain zip code, you can "find all cities in a zip code." The results will list not only the official name of the cities and towns within the zip code, but also other acceptable and unacceptable names for that area. This is handy if you can't read someone's handwriting or if a friend abbreviated the name of his or her town.

Zip-Codes.com
This site is fun. You can search zip codes, area codes, states, counties, or towns/cities. The information on this site is organized by zip code, so you will notice that the zip code in the results of other searches is a link. Once you click on the link, you will find demographic information, the area code, longitude and latitude, elevation, a local street map, and other facts for that zip code location. You can also search for the distance between two zip codes or the zip codes within a certain radius of the one you enter.

ZipInfo.com
If you Google "zip codes" you will find this site. However, the information in the free zip code lookup is incomplete because it is a sample of the company's zip code database, which is available for purchase. If you find your way to this site and try to look up the zip code for Nashua, you will not find it.

NANPA
NANPA, the North American Numbering Plan Administration, is the organization that assigns area codes. This site offers information about NANPA and the numbering system, as well as a searchable database of area codes in the United States. NANPA allows you to find an area code by clicking on a map, or you can choose "tools" from the dropdown menu on the side of the screen to do an area code search or a city/town search. The area code search gives you information about a particular area code, such as its geographic location, whether it is an overlay code, and its time zone. The city/town search allows you to either enter the name of the city/town to find its area code, or the area code to find the list of cities and towns it covers.

All Area Codes
All Area Codes offers two ways to match locations and area codes in the United States and Canada. By clicking on a state name, you will find its area codes and the cities located within the area codes. The site also offers a numeric listing of area codes. If you have a phone number with an unfamiliar area code, this will tell you in which state the area code is located.

WhitePages.com
In addition to searches for addresses and phone numbers (which include area codes and zip codes), the WhitePages.com site has a search specifically for area codes and zip codes. Click on the "area and zip code" tab to search for an area code or zip code by entering a city and state, or do a reverse search by entering an area code or zip code that you already have. The tab also includes a link to a US area code map and a list of international codes.