Using a Wi-Fi extender can have some impact on your internet speed. The extender works by capturing the existing Wi-Fi signal and rebroadcasting it to extend the coverage. However, this process may lead to a slight reduction in speed because the extender needs to relay the signal. The extent of the speed impact depends on the extender's quality and how well it's positioned in relation to the router. High-quality extenders and proper placement can minimize any speed loss.