Today, my boss asked me to find out why in TM bill show many callers are from Kelantan/ Terengganu/ Pahang despite we are operating in Kuala Lumpur and company activities are in southern region only. While running through that issue, I have found a pretty useful website (although it may not relevant to the work!). It is International Numbering Plans. The best part is, you can know the caller is from which area based on the telephone numbers.

International Numbering Plans is specialised in world-wide (tele)communications related numbering plans, and offers a range of on-line services for a variety of market segments in the global telecommunications sector. Most on-line services are free of charge for personal or limited use. For professional and business use various subscriptions are available. There are number analysis tools, on-line numbering plans, on-line dialling tools, and databases available for downloads.

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