The exchange rate between the US dollar and the Nigerian naira is constantly fluctuating. To determine how much a 100-dollar Amazon 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, central bank policies, and market sentiment. Financial institutions and currency exchange platforms provide the most up-to-date rates. By looking at these sources, one can find out the precise value of 100 dollars in naira.
It's important to note that the value will change throughout the day as the market dynamics shift. So, when considering converting a 100-dollar Amazon gift card to naira, it's advisable to get the latest rate at the time of the transaction to ensure an accurate conversion.