Slow Wi-Fi can come from the internet connection, distance from the router, interference, too many devices, or aging equipment. First separate a Wi-Fi problem from an internet-service problem.
Compare wired and Wi-Fi performance if possible
If a wired device is also slow, the bottleneck may be the ISP, modem, or service plan. If only Wi-Fi is affected, focus on coverage and interference.
Test near and far from the router
A large improvement near the router points to coverage. Dense walls, metal, large objects, and multiple floors can weaken the signal.
Check whether slowness is time-dependent
Backups, streaming, game downloads, and video calls can saturate the connection. If every device slows at once, look for shared traffic.
Restart methodically and update
Restarting the modem and router can clear temporary faults, but it will not fix poor coverage. Keep firmware updated and consider repositioning or replacing obsolete equipment if the pattern persists.