Waveform’s free browser test checks latency while a connection is busy, not just idle, and can flag Bufferbloat in under a minute with an A+ to F grade.
Bufferbloat happens when routers queue too many packets under load, so a line showing 6ms or 15ms idle ping can jump to 200ms or even 500ms during uploads or downloads.
Upload-active latency is often the key number on home networks because upload capacity saturates faster, dragging down video calls, gaming and voice chat even when headline speeds look strong.
An 85% to 90% speed cap with Smart Queue Management—especially CAKE or FQ-CoDel—can keep queues short and bring loaded latency closer to idle levels, even if peak throughput falls slightly.
Many ISP-supplied routers lack proper SQM controls, so users may need bridge mode or third-party firmware such as OpenWrt, pfSense or OPNsense to fix congestion rather than just buy more bandwidth.