Why Is My Internet so Slow and What Can I Do About It?

1. Weak Wi‑Fi signal or interference

Wondering why your internet drags in the bedroom but flies in the kitchen? Chances are, your signal strength (RSSI) is too low. Things like distance from the router, reinforced concrete walls can weaken the signal until your speed tank. It’s only part of the story. In multi-dwelling environments, overlapping channels from nearby access points create considerable contention.

When multiple routers broadcast on the same channel — Channel 6 is a frequent example — every frame must wait its turn, reducing throughput for all devices. Partially overlapping channels, such as 4 or 8, compound the problem by introducing cross-channel noise that forces repeated packet retransmissions.

As a practical reference, Cisco commonly uses about −67 dBm together with an SNR of at least 25 dB as a design target for applications that need reliable, timely packet delivery. Around −70 dBm may still be perfectly usable for lighter tasks such as email and web browsing. These are useful troubleshooting reference points, not hard pass/fail boundaries — the client device, interference level, and application still matter.

That distinction is important. A device can show a seemingly decent signal and still perform badly if the surrounding RF environment is noisy. RSSI tells you how strong the received signal is; it does not tell you the whole story about connection quality.

NetSpot’s Inspector Mode shows every Wi-Fi network it detects — including hidden SSIDs — in real time and lists each one’s channel, channel width, and signal strength. This visibility allows you to identify congestion quickly and select the least-occupied channel.

If you discover no truly free channels, choose one that fully overlaps with the dominant networks — Channel 1 or 11, for instance — As a result, Carrier Sense Multiple Access with Collision Avoidance (CSMA/CA) controls channel access and can coordinate transmissions more efficiently than on a partially overlapping channel.

After selecting a clearer channel, reassign high-bandwidth devices to the 5 GHz or 6 GHz bands, whose wider channels and lower congestion usually deliver higher data rates, albeit over shorter distances. Should interference persist, relocate the client device closer to the router or employ a wired Ethernet connection to eliminate the wireless bottleneck entirely.

The available 6 GHz spectrum depends on the regulatory domain. In the United States, the FCC made 1,200 MHz of the 6 GHz band available for unlicensed use — a major reason Wi-Fi 6E and Wi-Fi 7 can offer substantially more channel space than 2.4 GHz. More spectrum helps with congestion, but it doesn’t remove the usual range trade-off at higher frequencies.

2. Poor Router Placement

Where you place your router is arguably the most important factor that determines your internet speed. The further away from your router you get, the weaker the Wi-Fi signal, so you should find a place from where your router can cover your whole house or apartment and not just a room or two. NetSpot’s survey mode can help you see which rooms are covered with a strong Wi-Fi signal and which are barely covered at all.

Load or sketch a floor plan, walk through each room, and the app automatically records detailed Wi-Fi signal for every network it sees. When you finish, NetSpot builds a Wi-Fi heatmap that highlights strong and weak areas at a glance.

Move the router to a high, open shelf near the centre of the house — well clear of microwaves, metal cabinets, and thick walls — then run a quick follow-up survey to confirm the new spot delivers fast, even coverage everywhere you need it.

For a more useful before-and-after comparison, keep the survey conditions similar and repeat measurements in the same areas after moving the router. The goal isn’t just to make one weak room turn red on a heatmap. Check whether the change improved overall coverage without creating a new weak spot somewhere else.

3. Overloaded or outdated router

Even the fastest plan can’t outrun a decade‑old Wi‑Fi 4 box. Older hardware can become a bottleneck because of slower radios, limited processing capacity, or outdated firmware — especially once many devices are active at the same time.

If speed nosedives when several devices stream at once, flash the newest firmware and check whether the router itself has become the limiting factor before replacing it. Moving to a newer Wi-Fi generation can bring better efficiency and capacity, while WiFi 6E adds access to 6 GHz and WiFi 7 can add features such as wider channels and Multi-Link Operation on compatible hardware.

4. Local bandwidth hogs

Silent cloud syncs, OS updates, or someone binge‑watching 4 K videos devour capacity. Task Manager or Activity Monitor shows real‑time usage so you can pause anything greedy.

Don’t look only at downloads. Upload saturation can be particularly disruptive on asymmetric broadband plans, where upload capacity is much lower than download capacity. A large cloud backup can fill that smaller upstream pipe and make video calls, games, and even ordinary browsing feel sluggish.

Throttling background jobs often fixes the “why is my internet so slow right now” problem.

5. External Bottlenecks: Server Limits and Slow DNS

Sometimes the slowdown is completely outside your network. A host can throttle each client or buckle under peak demand, so even a gigabit line crawls while that server doles out data at a trickle. The quick test is to grab a large file from a known fast mirror — Steam, Google Drive, or a local IX test repo — and see whether it fills your pipe.

If the alternate source flies while the original limps, the bottleneck is on the server side; choosing another mirror, scheduling the download for off-peak hours, or using a multi-threaded downloader usually solves it.

Delays can also start one step earlier, during DNS resolution. An overloaded or distant DNS resolver keeps your browser waiting before the first byte ever arrives, making pages feel sluggish even though the subsequent transfer would be fast.

Point your router or device at a quicker public resolver such as Google Public DNS (8.8.8.8) or Cloudflare 1.1.1.1 and retry. When a new DNS cuts page-load times but large downloads remain slow, you’ve only fixed lookup latency — the host itself is still the choke point. If neither change helps, the problem lives on your side of the link or with the ISP, so resume local troubleshooting.

6. Router Hardware or Firmware Issues

Have you tried turning your router off and on again? If not, you definitely should. A full power cycle often revives slow connections because it clears volatile memory and reloads the operating system. Consumer-grade routers that run non-stop for weeks can overheat, develop memory leaks, or slip into unstable states that throttle throughput.

Restarting can restore normal performance when a temporary software or resource problem is responsible. If performance rebounds only briefly — or not at all — look deeper. Outdated firmware or failing components may be responsible. Check your router maker’s support page, follow the troubleshooting guide, and install the latest firmware to fix known bugs and security flaws.

Inspect power and Ethernet cables for damage, confirm each port negotiates at its rated speed, and run another speed test. Persistent issues after these steps point to hardware failure; in that case, replacement is the most reliable fix for stable, high-speed connectivity.

7. High latency and messy routing

Long, unstable paths inflate ping and jitter, throttling TCP throughput. A traceroute can help show where latency starts to rise. A VPN can sometimes change the route and bypass a problematic path, but it can also add latency of its own, so treat it as a test rather than a guaranteed fix. Changing DNS generally won’t “shorten” the network route itself, although DNS can influence which CDN endpoint some services select.

Run another speed test after each tweak. Compare the result with your original baseline and with the speed your ISP actually delivers over a wired connection. When your numbers exceed the “comfortable” column above, you can finally stop googling why is my internet so slow — your line is delivering the speed you pay for.

8. ISP-Side Issues

At the end of the day, your internet speed depends on your internet service provider just as much as it depends on you. If repeated wired tests show the same slowdown across several devices, and you’ve ruled out heavy local traffic and equipment problems, it’s time to bring the evidence to your ISP.

Most carriers offer phone, chat, or email support; presenting clear evidence speeds up escalation, prompts a line test, and, when necessary, gets a technician dispatched to address network-side faults. Until the ISP corrects the issue, there is little more you can do on your end, so documenting the problem thoroughly is your strongest leverage.

Time-of-day data can be especially useful here. Evening congestion is real, but a dramatic nightly collapse shouldn’t automatically be dismissed as “normal.” In Ofcom’s March 2023 measurements, the average download rate across tested UK connections during the 8–10 p.m. peak period was 67.7 Mbps — about 95% of the 71.0 Mbps average maximum.

Full-fibre connections showed the smallest peak-time congestion effect. So, if your own wired connection repeatedly falls from 300 Mbps to 30 Mbps at the same time every evening, that pattern is worth documenting and escalating.