 50 paise to 1 rupee per minute 
250, so a 4 minute call on WhatsApp will cost you around one rupee. In India, WhatsApp call is definitely cheaper – A minute of WhatsApp call will cost you around 25 paise, while a normal mobile voice call will cost you anywhere between 50 paise to 1 rupee per minute depending on the plan that you use. These voice calls run over your data connection, and consume about 470 kilobytes (KB) per minute for each user. With a per-minute measure of data usage, it is possible to calculate a per-minute cost for a WhatsApp voice call. This means it can be compared to the normal voice call cost of mobile operators. Verdict. In India, WhatsApp call is definitely cheaper – A minute of WhatsApp call will cost you around 25 paise, while a normal mobile voice call will cost you anywhere between 50 paise to 1 rupee per minute depending on the plan that you use. We spoke for 15 minutes and for those 15 minutes the WhatsApp on our phone consumed around 12MB data. This means: -- If you are paying regular charges for data on a prepaid Airtel connection, 15 minutes of WhatsApp calls will cost you: Around Rs 50. This is based on the standard data charges -- 4 paisa per 10KB -- from Airtel that are exorbitantly high. As a thumb rule, you can conclude that one minute of WhatsApp call will consume roughly 1mb of data. So, you need to simply calculate, depending on the cost of the data pack as to how much it will cost you. On Idea Cellular, 1GB data pack costs around Rs. Subscribe. WhatsApp voice calls will cost South African mobile data bundle users as little as 2c per minute, or as much as 92c per minute in out-of-bundle or ad-hoc data usage.
http://trak.in/tags/business/2015/05/13/whatsapp-voice-call-costs-cheap/ http://mybroadband.co.za/news/smartphones/122634-prices-compared-whatsapp-calling-vs-mobile-voice.html http://trak.in/tags/business/2015/05/13/whatsapp-voice-call-costs-cheap/ http://indiatoday.intoday.in/technology/story/whatsapp-calling-feature-cost/1/424310.html http://trak.in/tags/business/2015/05/13/whatsapp-voice-call-costs-cheap/ http://mybroadband.co.za/news/smartphones/122106-the-data-cost-of-whatsapp-voice-calling-in-sa.html
cost of whatsapp call