ZIPKEY zipcodes and area codes

32-bit ZIPKEY is released!

I have released my 32-bit rewrite of ZIPKEY for Windows, and I have broken off the zipkey.com Web site to have its own home page, different from eji.com. Click here to go to the new zipkey.com home page.


ZIPKEY is an incredibly small, fast, easy-to-use utility that lets you look up zipcodes, area codes, city names, and time zones within the USA. You can purchase and download ZIPKEY within a few minutes.

ZIPKEY's database contains all 41000+ zipcodes in the USA, with associated city and state names, telephone area codes, and timezones. If this data were loaded into an ordinary database table, it would occupy several megabytes. But the ZIPKEY program is constructed like a fine Swiss watch, with every machine instruction handed coded, and with the data custom-compressed. As a result, the entire package occupies only about a quarter of a megabyte!

You can read on for more details, or click here to purchase the software and see for yourself.


updated November 8 ©2004 --- Eric's home page --- A86/D86 --- Other authors and sites --- E-mail Eric
  • Overview of ZIPKEY
  • Area code explosion in progress
  • Raw data available
  • Download ZIPKEY
  • How to purchase ZIPKEY
  • Frequently Asked Questions
  • Overview of ZIPKEY

    ZIPKEY is a complete city-level directory of 5-digit United States zipcodes, 3-digit telephone area codes, and time zones, combined with a keyboard enhancement program. The goal of ZIPKEY is to provide enough power and flexibility so that no one with a Windows-based computer will ever again have to manually type in the name of a United States city or town (at least not one big enough to have its own zipcode).

    When run from your desktop, ZIPKEY allows you to instantly access any of the 42000+ zipcodes in the directory, searching by zipcode, state-and-city, city-only, or area code. If you want to use ZIPKEY just to occasionally look up a zipcode or area code, just double-click on the ZIPKEY icon, and follow the prompts.

    ZIPKEY achieves its full power when placed resident in memory. In this mode, you can invoke ZIPKEY from within any other program. You can type just a 5-digit zipcode, and ZIPKEY will make the program you're running think that you have typed any or all of the following: the city name, the state name and/or abbreviation, the zipcode, the area code, the time zone, and any other combination of fixed keystrokes. This "keystroke output" can be in any format that you wish.

    ZIPKEY is completely configurable. You can specify the "hotkey" that will invoke ZIPKEY when you're running another program. You can also specify alternate hotkeys to allow any number of different formats when ZIPKEY feeds the city/state/zip back through your keyboard.

    ZIPKEY has a sophisticated abbreviation algorithm, allowing you to specify a limit to the length of the city name, so that it will fit into a fixed field.

    Internally, ZIPKEY is a unique software creation. Every detail is crafted like a fine Swiss watch. All the machine instructions of the ZIPKEY program are hand-coded in assembly language, optimized for high speed and incredibly small size. ZIPKEY's database is based on data from numerous sources, including the U.S. Postal Service. It has been extensively cross-checked, to ensure accuracy and consistency. All changes to the database are reviewed by human eyes. The data is stored using a custom-designed compression scheme, providing for maximum compaction while retaining instant access. It occupies less than 122K bytes -- less than 3 bytes per entry, which is at least ten times smaller than the space the data would occupy in an ordinary database program.

    ZIPKEY has been a highly successful DOS application since 1989, and a 16-bit Windows application since 1998. This version of ZIPKEY is a complete rewrite as a native, 32-bit Windows application. Hotkey configuration and testing are now part of the Windows-based ZIPKEY program, and are easier than ever. Keystroke playback sequences can be edited on the screen, and the editing window can remain open while the hotkey is tested and if necessary modified to work with your applications.


    Raw data available

    ZIPKEY's database is normally sent to you in a encrypted file named ZipData, that only the ZIPKEY program can make any sense out of. You might wish to have the data available in a comma-delimited, ASCII text file that you can import into programs such as Access. This file is available for $105, licensed for access by up to 5 computers, with quarterly updates for one year.



    Buy now, single copy only $25 --- or --- Try free for 30 days

    Eric Isaacson Software
    416 E. University St.
    Bloomington, IN 47401-4739


    Eric's home page --- ZIPKEY --- A86/D86 --- Other authors and sites --- E-mail Eric