Best way of locating users [closed]

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how can i do this or like this ?

Is there any free web service to detect location of users ?

I want to use this in a webpage

Avoid maintaining a huge database of IP's and their locations!

My Priorities are : The service should be : 1.Free 2.Most Accurate

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From http://blog.programmableweb.com/2009/03/31/3-free-ways-to-geolocate-by-ip/ I got

Hostip.info is a community-powered database of IP mapping. Its REST API is easy to incorporate into server-side code, with several options for the type of output. Check out our hostip.info API profile, where you can see the mashups already using this API.

MaxMind-Geo Lite is an API of a different sort. Rather than call to a web service, its free version is distributed as a binary. There are open source libraries for common programming languages to access the IP data.

Also see http://www.eggheadcafe.com/articles/20051109.asp

Similar question : https://stackoverflow.com/questions/283016/know-a-good-ip-address-geolocation-service

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I use GeoIP Country Lite. Every month they publish updates to the database and they claim 99.5% accuracy. It is trivial to use as they also provide library code to query the database.

MaxMind also provide city based lookups if you need higher resolution than by country.

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The HTML5 Geolocation API works in never browsers (Safari, Chrome, Firefox), though it requires some kind of location service on the computer. I would use this first and then fallback on location by IP if HTML5 Geolocation is't available. Sample code:

if (navigator.geolocation) {
  navigator.geolocation.getCurrentPosition(function (pos) {
    console.log([pos.latitude, pos.longitude]);
  }, function (err) { 
    // Do something else, IP location based?
  });
} else {
  // Do something else, IP location based?
}

To find the Country, City and even address of the user you can use Google Maps Geocoding API

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This works great as far I tested it.

Get an api key from ipinfodb.org

var Geolocation = new geolocate(false, true);
Geolocation.checkcookie(function() {
    alert('Visitor latitude code : ' + Geolocation.getField('Latitude'));
    alert('Visitor Longitude code : ' + Geolocation.getField('Longitude'));
});

function geolocate(timezone, cityPrecision) {
    alert("Using IPInfoDB");
    var key = 'your api code';
    var api = (cityPrecision) ? "ip_query.php" : "ip_query_country.php";
    var domain = 'api.ipinfodb.com';
    var version = 'v2';
    var url = "http://" + domain + "/" + version + "/" + api + "?key=" + key + "&output=json" + ((timezone) ? "&timezone=true" : "&timezone=false" ) + "&callback=?";
    var geodata;
    var JSON = JSON || {};

    // implement JSON.stringify serialization
    JSON.stringify = JSON.stringify || function (obj) {
        var t = typeof (obj);
        if (t != "object" || obj === null) {
            // simple data type
            if (t == "string") obj = '"'+obj+'"';
            return String(obj);
        } 
        else {
            // recurse array or object
            var n, v, json = [], arr = (obj && obj.constructor == Array);
            for (n in obj) {
                v = obj[n]; t = typeof(v);
                if (t == "string") v = '"'+v+'"';
                else if (t == "object" && v !== null) v = JSON.stringify(v);
                json.push((arr ? "" : '"' + n + '":') + String(v));
            }
            return (arr ? "[" : "{") + String(json) + (arr ? "]" : "}");
        }
    };

    // implement JSON.parse de-serialization
    JSON.parse = JSON.parse || function (str) {
        if (str === "") str = '""';
        eval("var p=" + str + ";");
        return p;
    };

    // Check if cookie already exist. If not, query IPInfoDB
    this.checkcookie = function(callback) {
        geolocationCookie = getCookie('geolocation');
        if (!geolocationCookie) {
            getGeolocation(callback);
        } 
        else {
            geodata = JSON.parse(geolocationCookie);
            callback();
        }
    }

    // Return a geolocation field
    this.getField = function(field) {
        try {
            return geodata[field];
        } catch(err) {}
    }

    // Request to IPInfoDB
    function getGeolocation(callback) {
        try {
            $.getJSON(url,
                    function(data){
                if (data['Status'] == 'OK') {
                    geodata = data;
                    JSONString = JSON.stringify(geodata);
                    setCookie('geolocation', JSONString, 365);
                    callback();
                }
            });
        } catch(err) {}
    }

    // Set the cookie
    function setCookie(c_name, value, expire) {
        var exdate=new Date();
        exdate.setDate(exdate.getDate()+expire);
        document.cookie = c_name+ "=" +escape(value) + ((expire==null) ? "" : ";expires="+exdate.toGMTString());
    }

    // Get the cookie content
    function getCookie(c_name) {
        if (document.cookie.length > 0 ) {
            c_start=document.cookie.indexOf(c_name + "=");
            if (c_start != -1){
                c_start=c_start + c_name.length+1;
                c_end=document.cookie.indexOf(";",c_start);
                if (c_end == -1) {
                    c_end=document.cookie.length;
                }
                return unescape(document.cookie.substring(c_start,c_end));
            }
        }
        return '';
    }
}