Where do your users come from: detecting user location on websites

Detecting your website user’s (approximate) location has huge benefits in providing relevant experience without them telling you anything. There are a couple of techniques available today that let you do that: a) detect approximate location by IP address b) detect more accurate location using WiFi base stations (and their MAC Addresses) c) Cell tower triangulation (mobile client only) d) GPS (mobile client only). If you limit the options purely for Web Browsers and Desktops, its just IP and WiFi based location detection that’s available today.

The IP Address based detection is less accurate but hassle free (your users don’t need to install anything); implementing such a solution usually means that you license an IP to Geo database to look up parts of IP address to calculate a latitude/longitude value; which is fairly simple thing to do. Having said that, if you are using Google Maps for your website, detecting user’s location using IP address has gotten much easier: Google maps announced that the developers can now detect user’s approximate location based on their IP address at the time of loading the map. According to the documentation, the implementation looks fairly straight forward:

//Load the map.
function loadMaps() {
    google.load(“maps”, “2”, {“callback” : mapsLoaded});

//Check if the client location is available. If it is set map center.
function mapsLoaded() {

    if (google.loader.ClientLocation &&
         google.loader.ClientLocation.latitude &&
           map.setCenter(new google.maps.LatLng(google.loader.ClientLocation.latitude,
                                                             google.loader.ClientLocation.longitude), 13);

Obviously you can implement various ways to determine the zoom level based on the city/state level info – but you get the idea. In my previous job, I have developed both IP and WiFi based location detection techniques that are being used in Virtual Earth/Live Maps today – I hope to see them open up those via APIs too.

Now the other method of detecting location based on radio stations (WiFi mostly) – this usually requires some kind of installation since browsers cannot access the radio stack by themselves and they need a handshake from some kind of a plugin to scan that information and provide it back to the browsers. Skyhook is the only commercial provider that is currently providing the tools/plug-ins to use this method today. Alternatively one can obtain a crowd-sourced database full of WiFi Hotspots and their locations and write the plugin layers on top of it. Either way the depth and recency of WiFi hotspot information determines the accuracy of the location information.

New release update on Center’d

We had a new release this morning on Center’d that included a set of new planning utilities as well as a number of upgrades to the existing features.


A detailed post on our official blog from Jen is up tonight. Obviously as a “local geek” and a former mapping guy, I would like to highlight the local search updates that Jen talked about:


“We also made some improvements to our local search to help you find the right places and service providers for whatever you might be looking for at this time of year (for our family, it was an orthodontist). Our search now combines aggregate ratings from across the web with the information and tags you and your friends have made on Center’d to provide even more relevant results.  If you are a Center’d member, do a search and you will see higher rankings for the places you and your friends have saved.  Want to make the results even better?  Save and tag the places you like.  I have saved everything from our pediatrician to our favorite car wash to help other people more easily find things they might like too. Give it a shot by connecting to a Center’d team member, and check out some of the places we like.”


Bringing local search into an actionable form is what we do at Center’d – in future you will see how we are going to integrate the personalized (or social) local search into planning tools in a more cohesive way. In the mean time, I would love it if you can give our planning tools and our search a try and send us feedback!


Chandu Thota

Co-Founder & CTO