A router that seems slower after several days needs a comparison, not an automatic weekly-reboot rule. Uptime by itself does not establish a fault. Competing traffic, wireless conditions, firmware problems, thermal conditions and the internet connection can produce similar symptoms. A restart that helps temporarily is useful evidence, but it does not prove that “cache buildup” was the cause.
Use the internet speed test to record a browser baseline when the problem occurs. Keep the device, connection and test conditions consistent. The test cannot read your router’s memory, temperature or internal connection table.
Compare the pattern before changing settings
| Pattern | First useful comparison | Avoid concluding |
|---|---|---|
| Only one device is slow | Another device at the same time and place; then the affected device on a second supported connection. | That router uptime is responsible for every device’s performance. |
| Wi-Fi is slow but Ethernet is consistently better | The same device close to the access point, with the band and location recorded. | That the broadband plan alone explains the wireless difference. |
| Both Wi-Fi and Ethernet slow together | Background traffic, another time period, modem/ISP status and the provider’s supported diagnostic procedure. | That a browser test alone distinguishes router, modem and ISP causes. |
| Calls lag mainly during uploads or downloads | Idle versus loaded timing, followed by the real application’s own diagnostics. | That every slowdown requires replacement hardware. |
| The symptom returns after a restart | Time until recurrence, firmware version, connected activity and available device logs. | That regular rebooting has fixed the underlying fault. |
Check traffic, placement and firmware
Review downloads, backups, camera uploads and other activity you recognise. Pause one optional transfer for a comparison. If your router exposes traffic or system diagnostics, consult its model-specific instructions; available counters differ. Do not enter an administrator password into a speed-test page or assume a browser can inspect the router automatically.
TP-Link’s slow-speed guidance distinguishes wired and wireless symptoms and identifies restricted ventilation or direct sunlight as possible contributors. Follow your own model’s placement instructions and keep its ventilation openings clear. A warm enclosure alone is not a measurement of thermal throttling.
Check the manufacturer’s support page for the exact hardware revision and approved firmware. Use its update procedure and save a settings backup where supported. Firmware is a possible line of investigation, not a promise that an update will increase the internet plan’s speed. For ISP-managed equipment, use the provider’s guidance.
Use a restart as one controlled comparison
- Record the time, affected devices, connection type and repeated results before restarting. Note whether transfers are active.
- Save work and choose a suitable time. ASUS documents that a router reboot disconnects connected devices and may take several minutes.
- Use your device maker’s supported restart procedure. A restart is different from a factory reset, which can erase configuration.
- After the connection is ready, repeat under comparable conditions. A change in endpoint, background traffic or test time can also affect the result.
- If the problem recurs, record when and what changed. Share that history with the router maker or ISP rather than treating repeated restarts as a diagnosis.
No universal daily, weekly or fortnightly restart interval follows from these observations. Follow documented requirements for your particular equipment. Investigate unexpectedly frequent restarts or repeated loss of service.
Choose the next check
- Location-dependent Wi-Fi: compare one device with the Wi-Fi room comparison.
- Slowdowns during transfers: use the loaded-latency check and confirm symptoms in the affected app.
- Unsure where to start: follow the slow-internet troubleshooter for a question-led next step.
- Need broader context: read what causes slow internet and how a router can affect speed.
Frequently asked questions
Does a router inevitably get slower the longer it stays on?
No conclusion about a specific fault follows from uptime alone. Compare the symptom, traffic, local connection and manufacturer diagnostics. A recurring software fault is one possibility; it is not established by the date of the last restart.
If rebooting helps, does that prove the router was out of memory?
No. A restart changes several states and reconnects devices. Without relevant device diagnostics, the observation does not isolate memory, wireless conditions, traffic or an upstream event.
Sources and further help
Manufacturer guidance checked 22 October 2026; follow the instructions for your own model.