Ofcom are the definitive source for this information, as the official regulator.
There are also other more user-friendly sites around.
If you look at maps, you will not find area codes. Area codes can be found on area code locator websites. Another place to find area codes is in the telephone directory.
get your postal code from here : http://find-postalcode.com/ and putting it in your account
Here is a list of all telephone area codes ("claves LADA") in Mexico, from the Mexican government: http://www.sre.gob.mx/austin/Util/LadasMexico.html (The column labeled "clave actual" is the current area code. The telephone country code for Mexico is +52, and you must also insert the prefix '1' between the country code and the area code when calling a mobile phone or cell phone.)
In the UK, area code 020 is London, but there are no numbers beginning with 020 2. Other countries may have similar telephone area codes.
I can find no indication that the area code for Ghaziabad was ever 085. All current area codes beginning with 085 are in Andhra Pradesh, not Uttar Pradesh, halfway across the country. The area code for Ghaziabad is 0120.
It depends on what country. There are lists of STD Codes (telephone area codes) for different countries on a variety of websites. See the related links below for a few examples.
The same local telephone number can exist in many different area codes. (After all, that's the whole point of area codes.) If you know where the telephone number is from, and if that place has only one area code, you can find out that way.
You can find several listings of telephone country codes on the web; see the related links below.
(See the related links.)There are several websites that one can find the country codes for calling international numbers.http://LincMad.com/countrycodes.html
There are no 9-digit telephone area codes, anywhere in the world. If you mean your 9-digit U.S. ZIP Code (postal code), try the related link.
Try countrycode.org. There, you can search for any country code that exists by name or number. If you try allareacodes.com you can get any area code within the United States and territories.
There is a list of area codes for the US and Canada on LincMad.com; see the related link.