Packet loss occurs when one or more data packets fail to arrive at their intended destination during transmission over a network. It's measured as a percentage: for example, 1% packet loss means one in every 100 packets goes missing. The packets that get through do arrive intact; the issue is simply that some never complete the journey.
Packet loss happens for several reasons. Network congestion is the most common culprit: when too much data tries to flow through a router or switch at once, buffers fill up and packets get discarded. Interference on wireless networks (from microwaves, cordless phones, or neighbouring Wi-Fi signals) can corrupt packets in transit. Faulty hardware, software bugs, or unstable connections also cause packets to drop. Distance and signal strength matter on Wi-Fi: move further from your router and packet loss may increase.
In real life, a little packet loss often goes unnoticed. Web browsing tolerates it well because lost packets are simply re-requested and resent. Video streaming services adapt by reducing quality. But gaming, video calls, and VoIP become noticeably laggy or choppy at even 1% loss. Online competitive games may feel unplayable at 3% or higher.
When shopping for a broadband package or network equipment, low packet loss is a sign of stability. Check your own connection using a ping test to a reliable server (your internet service provider's gateway is a good target): packet loss should be 0% under normal conditions. If you're seeing consistent loss, it suggests either network congestion in your area, a weak Wi-Fi signal, or a faulty router. Upgrading to a newer router, moving closer to it, or switching to a wired connection often fixes it.