Frequently Asked Questions about

Where do you get your data?

I get it from various sources. Most of it comes from NANPA and the CNAC, as well as various regulatory information pages, CLEC notifications posted on ILEC websites, and user submissions. :-)

How often do you obtain new data to reflect changes in number assignments?

I do so generally once or twice a week. I also do it periodically when I read about a new area code assignment, etc. The date I last updated the data is at the top of the screen, and is only changed by the process that I use to update the site, not minor changes in the switch data, etc.

I think I found something wrong! Who do I tell?

If you think it's wrong, it probably is. The data I have is altogether pretty damn good, but it often falls behind the real world by a few months. Yay for bureacracies. Send me an email at support at and I'll look into it.
If you're the telco involved, update it with NANPA and probably BIRRDS too, I'm not sure where the original source NANPA uses is. I'd apreciate it if you sent me the contents of your update as a courtesy.
But I should point out that I am not affiliated with Telcordia, and I cannot update them, or NANPA for you. Log into NAS and make the change yourself. If you need an account you can create one here. Again, note that I'm not affiliated with Telcordia or NANPA.

I have a copy of something I think you need to see.

Send it here. I'd probably love to see what it is. From cool pictures, to interesting data, I'll only report it if you ask, and I won't identify you unless you ask me to. This is not to say I accept proprietary data, but it's to say that if I recieved it, I wouldn't ID you to your employer or anything like that. ;-)

Why does the map thing not display my location properly?

I don't actually maintain the mapping data, Google does. If it's wrong, blame the sources. Oh, and some of the central offices are geocoded using V + H, changed to lat/lon. This introduces up to a quarter mile of error sometimes. These are actually really rare, since I maintain my own geocoding database for running this.

Is there geospatial data for exchange boundaries / Why can't I look up street addresses and find out what ratecenter or wirecenter someone is in / Why can't I search by any arbitrary zipcode rather than just ones containing central offices? / Why don't you have local calling area data?

Ratecenters and wirecenters, and I'm saying this as diplomatically as I can, are a gigantic mess of crap. Many ratecenter definitions are based off of county plat maps, local landmarks, and sometimes even stuff like "200 feet south of the intersection of X and Y street." Even worse, some contain exceptions based on specific street addresses, because they existed before the current ratecenter/wirecenter was created, and their lines are grandfathered in the old exchange. If you think I'm joking, try Ma Bell/Michigan Bell/Ameritech Michigan/SBC/AT&T/Whatever they're calling themselves this week's Michigan exchange areas. Sounds almost doable, right? Now try CenturyTel's Michigan exchange areas. Fun, huh? Now do it for the other exchange carriers in MI (lucky for you, you only have to find tariffs for the ones marked "ILEC" if you want boundary maps!), then try it for all 50 states.

The other thing is Zipcodes. If there's anything more arbitrary than Rate/Wirecenters, it's zip codes. These can change at the whim of the postal service, and are based on the routes mail carriers use. If your current mail carrier retires, and they decide to retool the way their old route is served, you can find that you're suddenly in a new zip code, because your mail actually comes from a different post office. Sure, it's rare if you only look at the liklihood of it happening to you, but it's not rare overall, as the postal service is always trying to retool things to be more efficient. For example, my childhood home was served telephone service out of the Grand Haven, MI wirecenter. Our street address had a Spring Lake, MI zipcode. The town we lived in was Ferrysburg, which actually has its own post office but it only does local delivery to some local businesses, and otherwise only runs PO boxes. What zipcode should I give? Why? A friend of mine lives in Madison Heights, MI. He has a Madison Heights Zipcode, but is served from Troy Main wirecenter, with a Royal Oak ratecenter. Royal Oak has its own central office, which I am served from. We live two blocks apart in the same square mile. What do I give for him, and why? Now magnify these on a national scale.

Other companies may try to guess and come up with something good enough for horseshoes and hand grenades, but I don't feel comfortable selling something I'm not confident in. If you're using zipcodes as some sort of correlator with phone numbers, stop, you really shouldn't. Down that road is nothing but madness.

Almost all of the above also applies to local calling areas. There's no uniform law in the US that defines what a local calling area is. In some states, it has to do with a physical radius measured in miles, and for example, in Michigan the law states that the local calling area is the ratecenter and any ratecenter it touches. Some states are basically "whatever the commission determines is in the public interest". Creating and maintaining this data requires that you read every tariff in the United States, and then track any changes. That'd be great if there were a central tariff repository in the US (there's not, there's at least 50 different ones, one per state. And often there's more, as in some states the carriers have them on their website, and in other states, the state maintains a repository. Good times!).

I love this site! You should put banner ads up so you can make money with it!

Thanks, but no. Two reasons:

  1. I work for a CLEC. I try not to commingle that with running this site, but as they pay the majority of my bills, and allow me to live comfortably, I'm not going to advertise for a competitor, sorry. In return, you don't have to see ads for mine. Fair? :)
  2. This is a labor of love. I use the site as much as you do. Banner ads suck. They slow the page loads, they're ugly as hell, and they don't make any money anyway.
  3. I get enough from the rare paid user that I am not really want for money. But if you want to give me some, see below.

What do you currently do for a living? Do you work for a phone company or something?

When I started the site in 2001 I didn't. I do now. It's a CLEC headquartered in MI. We serve local and LD in MI,IL, and OH.

What hardware do you run this site on?

I ran the site for years on a Athlon XP 1900+ with 512MB of RAM and an 80GB drive, supplied by the nice folks at Internet 123.

It now runs on a virtual machine on a personally owned xenserver cluster. It is collocated in the collocation center of my employer, Clear Rate Communications.

The site is writen mod_perl.
The backend database is running MySQL. It's fast, and easy to setup and use. I don't feel like dealing with Oracle or any of the other free database servers.
All the servers involved in the site are running Debian Linux. I like Debian.
I want a copy of your data. Can I have a copy?

Not in its full form. I do offer downloads for certain stuff here. It's not free, but it's super cheap (Less than $15.00 a month, if you buy more than a month at a time. And I don't autobill, so there's no risk)

If you have a need for the data, I offer a few ways to get it.

I should warn you that the documented queries are a bit out of date. I have been working on revamping them. I do have some XML-RPC and SOAP APIs if you're interested. Send me an email.
Basically my preference would be to only query the data when you need it, and only query what you need. If you want a CSV of something, ask me, I almost always do it. My only concern is that I'll receive a bad reputation because people use my old data, and give me credit for it. If you're going to do something cool, talk to me and I'll help you find a way to make sure your information is always current.

It says at the top of the screen that the site is in "Maintainance mode". What does that mean?

That means that I am doing some work on the database server, and the information may be old, inaccurate, or incomplete, or that the site will be very slow. I may end up restricting some queries while in maintainance mode. Come back in an hour and everything should be cool.

So what motivated you to be interested in the telecommunications business? Are you insane?

Yea, it's from when I was little and was playing with the phone lines, and took 48VDC across the tongue. No, but seriously, I have always been interested in the telecommunications field, either when I was 12 and building my own telephone set (that actually worked on real phone lines), or when I was bored one day and curious, and came up with this site when I couldn't find the information I wanted.

I've used this site alot, and it's been *so* helpful to me and/or my company. How can I ever repay you?

Well, I'd really love a facilities tour, if it's within driving distance of Detroit. That would totally rock my world. 8-)
I'd prefer you donate monetarily by subscribing to a paid account. It's not autorenewing or autobilling, and you get something in return (and I get more of the money in a more convenient way). If this isn't something you want to do, you can send me a donation by paypal, but if I get it there, it's likely to be spent on eBay :-) )

This looks like alot of data, do you input it all by hand or do you have scripts?

Some of it is hand entered. Most of it is input by scripts. A certain group of people have made sizeable contributions to this site in some way, shape or form, but to date I'm the only person who manipulates the data supplied or retrieved, and wrangles with it until it gets in the database, where it belongs. :-)

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