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There is quite a bit of difference between the 2000 ZCTA's that can be downloaded from the census bureau and the ones that can be extracted from the 2005SE Tiger/Line database. There are changes to just about every zip code plus the 2005SE extract has a lot more detail.

To view these differences, check out this tool:

http://maps.huge.info/newzips.htm

The ZCTA Zip Code polygons that are used in the zip code map have been updated to those found in the Tiger/Line 2005SE dataset. These updated zip codes reflect a much more accurate picture of the actual zip codes. The old zip code boundary map (zipv0.htm) will still use the original 2000 census data, so use that page if you need the original data.

You can compare the 2000 ZCTA's to the 2005SE ZCTA's using this page:

http://maps.huge.info/newzips.htm

It has been brought to my attention that there are some blank areas of the new maps, notably in Jefferson County, KY. I researched the problem and both to my consternation and delight, it is due to errors in the Tiger/Line data and not the program I wrote to resolve out the new ZCTA's.

The 2005SE Tiger/Line data for state 21, county 111 (Jefferson County, KY) has ZCTA's only for the bordering counties but none at all for the ZCTA's internal to the county. I guess somewhere along the line this information was lost. I can only hope that it will be added back in at some point.

In the event that other missing data is suspected, it can be confirmed by using the 2000 ZCTA vs. 2005SE ZCTA tool (http://maps.huge.info/newzips.htm) I wrote. Please report any problems of this nature to me using the contact form (click here).

I received a note back from the Census Bureau, Geographic Products Management Branch, regarding the data error I discovered. Turns out the Tiger/Line product is not at fault as I suspected. The fault, dear Brutus lies in ourselves, not the stars... Somehow, during the automated process of loading the Tiger/Line data, the "I" records for Jefferson County, KY didn't get loaded. I will have to write a program to verify the entire data set now.

Actually, this is both good news and bad. Good news in that the Tiger/Line data has been vindicated. Bad news in that there was a glitch in the automated process to load the data. Regardless, writing a verification program will give me greater confidence in the data.

You may use our programs to retrieve data in the form of XML files for use on your own maps or whatever purposes by using this syntax:

5 Digit ZCTA Zip Codes:

http://maps.huge.info/zipv0.pl?ZIP=<5 digit zip code here>

Example:

http://maps.huge.info/zipv0.pl?ZIP=32750

3 Digit ZCTA Zip Codes:

http://maps.huge.info/zip3.pl?ZIP3=<3 digit zip code here>

http://maps.huge.info/zip3.pl?ZIP3=327

A new version of the zip code boundary map has been released today! This one displays actual USPS zip code areas instead of ones based on the Tiger/Line ZCTA's. The results are the most accurate free USPS zip code boundary maps available anywhere on the internet. These new maps are up to date as of November/2006 and will be updated quarterly.

USPS Zip Code Boundary Maps

The usual 150 hits per every 120 minute limit applies to this map.

-John Coryat, USNaviguide.com

Officially, there is no such thing as a zip code boundary, a zip code area or any geographic representation of a zip code. To the USPS, a zip code is a delivery route, not an area. Here's a good explanation from the Census bureau comparing the ZCTA to the USPS Zip Code.

http://www.census.gov/geo/www/tiger/tigermap.html#ZIP

The difference between the 2000 census ZCTA and the 2005SE based ZCTA's is the age of the data. The 2005SE ZCTA's are dated as of December (or there abouts) 2003 and the 2000 census ZCTA's are sometime before 2000, probably 1998.

A new version of the ZCTA based Zip code map was released today. This one is based on the Tiger/Line 2006FE database which was released on 12/12/2006. In addition, the online program is now using a more up to date version of the search database that will result in fewer misses on zip codes. See ZCTA Boundary Maps to give it a test drive.

Also available today for license is a new version of the database, same price as the old one at $1000. See Sales Data for more information on products and pricing.

If you would like to add a link to your site that would directly bring up a map of a particular zip code, we have this facility in our system:

Example using zip code 38654

http://www.usnaviguide.com/zip.htm?z=38654

Please feel free to add this link to any of your sites. We certainly appreciate it!

The 2006SE ZCTA map has undergone an upgrade to show new imagery and more details. The colors have been switched from 100 random colors to just 8 pastels, which is more in line with standard mapping practices. The algorithm to compute colors is not perfect, a perfect one would have only used 5 colors, but 8 is pretty good. If anyone is interested in this algorithm, one I developed myself, I would be happy to share it. At some point it may be published as a Google Code article.

2006 ZCTA Zip Code Boundary Map

Our USPS Zip Code Polygon database has been updated! The new database is current as of 09/2007 and contains 31,581 zip code areas. Combine this database with our zip code bounding box product and you'll have a complete zip code depiction package. The new database comes as either shapefiles (one per state) or as a tab delimited file in PostgreSQL dump format. Importing this data into your MySQL, SQL Server or other database system is easily accomplished using the PostgreSQL format, your GIS program is probably best with the shapefiles.

The price for this product is $5000.00 and updates are $1250.00 available each quarter. Updates are not mandatory and contain a full database, so update only on your schedule, not ours.

If you've purchased a license to our ZCTA database already, there is a special price on these polygons of $4000.00 for a limited time (expires 12/31/2007).

See the data in action on this page: www.usnaviguide.com/zip.htm

We've released a new version of our USPS Zip Code tiles this week, they are the same data as the old version (01/2008) but are more detailed, better formed, faster and prettier.

The old version used a method that required each tile to be projected into the "World Mercator" projection on the fly, this caused some stretching of the image and some smearing at higher latitudes. It also caused more drag on performance as the processor needed to change the image fit the tile. In addition, there was one image group for every two zoom levels, which would lead to pixelation.

The new version has one image group for every zoom level from 5 to 14, zooms above 14 interpolate the image from zoom 14, so there is some pixelation at very high zooms. The new version also uses an improved method of load balancing, and as stated, is pre-projected into "World Mercator" for both faster processing and better image quality.

The new load balancing method uses the modulus 3 of the "x" tile to compute which tile server to use, the old method simply had different zoom levels on each server. The old method was more efficient for server disk space but resulted in slower performance, especially in IE. With the new method, all three servers are sending tiles to each client, which is much more efficient for server processing power and bandwidth. The resulting increase in server disk space turned out to be irrelevant.

The new version can be found as a link on the old version's page for now. http://www.usnaviguide.com/zip.htm

Here's a list of zip codes that have been added since 10/2006:

We've moved the new version out of beta mode into live, so now when you view the standard zip code map, it will use the new and improved image graphics.

Most people believe that a zip code only resides in a single state but that's not true. If you look at a list of zip codes, it will appear as if this is the case, but a close examination of address that belong in a particular zip will indicate otherwise. We've compiled a list of zip codes that branch across state lines:

zips_in_multiple_states.htm

It's not surprising given that a zip code is a delivery route (according to the USPS) and not an area so if it's more efficient for a postman to drive across the state line to deliver some mail, they're going to do it.

No new city based zip codes this month, but four new APO/DHS zip codes have been created:

09318 APO
09343 APO
20588 DHS
20598 DHS