Why is my internet slow? Free diagnosis
Answer three quick questions. We’ll test your speed, lag, stability and access to popular services — then tell you what’s wrong and what to fix first.
Checking your connection…
- Popular services
- Download & upload speed
- Lag & stability
- Analysis
The most common reasons internet is slow
| Cause | Typical signs | First fix |
|---|---|---|
| Weak Wi-Fi | Fast near the router, slow in other rooms; fine on a cable. | Move closer, use 5 GHz, add mesh Wi-Fi. |
| Busy connection | Lag and buffering when others stream, game or back up photos. | Pause big downloads; switch on QoS/SQM in the router. |
| Router needs a restart | Everything gradually slower, random drop-outs. | Off at the wall for 30 seconds, then on. |
| Line or provider fault | Slow or down even on a cable; red light on the fibre box. | Log a fault with clear test results. |
| Device problem | Only one phone or laptop is slow. | Restart, update, forget and rejoin Wi-Fi, disable VPN. |
| Peak-time congestion | Fine in the morning, slow every evening. | Test at different times and share the history with your provider. |
| Power cuts | Internet drops when the power goes, even with a backup. | Both the fibre box and router need backup power. |
How our diagnosis works
First we check whether your browser can reach popular services such as Google, WhatsApp, YouTube, Netflix, Microsoft 365 and Zoom. This shows whether your internet is working at all, and whether one specific service is the problem.
Next we run a data-saving speed test against Cloudflare servers in South Africa, measuring download and upload speed, ping, jitter and how much lag increases when your line is busy.
Finally, we compare the results with your answers — your connection type, whether you’re on Wi-Fi, and your package speed — and turn them into plain-English findings and a fix list in the order most likely to help.
When to contact your internet provider
Contact your provider if you’re slow or disconnected on a network cable after restarting your router, if your fibre box shows a red light, or if your speed is consistently under half your package at different times of day. Copy the report from the diagnosis — it includes your numbers, provider and IP address, which saves time with support. Our guide on how to log an internet fault explains what else to include.
Frequently asked questions
Why is my internet slow at night?
Evenings (roughly 6 pm to 11 pm) are peak time: more people stream and game at once, so mobile towers and some networks get congested. If your speed is fine in the morning but poor every evening — especially on a cable — share your test history with your provider.
Why is my Wi-Fi slow but my cable connection fast?
Wi-Fi loses speed through walls, floors and distance, and suffers interference from neighbours’ networks. Move the router to a central, raised spot, use the 5 GHz network when you’re close by, and consider mesh Wi-Fi for bigger homes. See our Wi-Fi guide.
Should I restart my router?
Yes — it fixes a surprising number of problems. Switch the router (and the fibre box, if it’s separate) off at the wall for 30 seconds, then on again. Give it 3–5 minutes to reconnect fully before testing.
How do I know if my provider has an outage?
If none of the services in the diagnosis are reachable and your router lights show a problem (often a red “LOS” light on fibre), it’s probably an outage or line fault. Check your provider’s app, WhatsApp line or social media, then log a fault.
Does the diagnosis use a lot of data?
No. It always runs the speed test in data-saver mode, so it uses roughly 15–60 MB at most — less on slower connections.
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