The exchange rate between the US dollar and the Nigerian naira is constantly fluctuating. To determine how much a 15-dollar Play Store gift card is worth in naira today, one needs to check the current exchange rate.

Exchange rates are influenced by various factors such as economic conditions, market demand, and central bank policies. Financial institutions and currency exchange platforms provide the most up-to-date rates. By looking at these sources, one can find out the specific conversion value.
It's important to note that the rate can change throughout the day. So, when trying to convert the 15-dollar gift card to naira, it's advisable to get the latest rate at the exact time of the conversion. This ensures an accurate calculation of how much naira the 15-dollar gift card will yield.