How to troubleshoot a slow wifi network at home

Whenever the internet feels slow, the first thing most people do is blame their Internet Service Provider (ISP). Sometimes that's right, but more often than not the problem is sitting in a closet or on a shelf in your house — the router itself. Before you call your ISP and let them talk you into a more expensive plan you don't need, here are a few quick checks you can easily do yourself.

I've helped a lot of friends and family chase down a slow connection, and the symptoms usually point pretty clearly at the router once you know what to look for.

Signs the router is the problem, not the ISP

A few patterns show up over and over:

• Speed is fine right next to the router, terrible two rooms away. That's a wireless coverage problem, not an internet problem. Your ISP could double your plan tomorrow and the far bedroom would still be slow.
• Things slow to a crawl every evening around 6–9 pm. That's usually channel congestion — your neighbors all got home, turned on their Wi-Fi, and now a dozen routers in range are stepping on each other.
• The router is more than 5 or 6 years old. Wi-Fi standards have moved on a couple of times since then, and the radios inside older routers genuinely don't keep up with newer phones and laptops.
• The router is hot to the touch. A router that runs hot is a router whose performance is degrading. Heat is hard on the components, and one that's been baking in a closet for years is often on its last legs.
• You have to reboot it every couple of weeks to get things working again. That's the router telling you it's tired.

None of those symptoms get fixed by paying your ISP more money. The tech on the phone will happily upsell you to a faster plan because that's what they sell, but if the bottleneck is the box in your closet, a faster plan just means more bandwidth your router can't deliver to the rest of the house.

The simple test sequence

Here's the order I run things in to figure out where the slowdown is happening.

1. Run a wired speed test. Plug a laptop directly into the router with an Ethernet cable and run a speed test at speedtest.net or fast.com. If this number is close to what your plan promises, your ISP is doing its job and the problem is on the wireless side.
2. Run a wireless speed test from the same spot. Unplug the cable and run the same test over Wi-Fi, standing right next to the router. If the wired number was good and this one is way lower, the router's wireless side is the bottleneck.
3. Walk around and test again. Run the same test from the spots in the house that feel slow. If speeds collapse as you move away, that's a coverage problem — distance, walls, or both.
4. Power-cycle the router. Unplug it for about 30 seconds and plug it back in. Wait a couple of minutes for it to fully come back up, then re-run the tests. If everything snaps back to normal, the router was struggling and you've bought yourself some time — but it'll happen again.
5. Check 2.4 GHz vs 5 GHz behavior. Most routers broadcast two networks. The 2.4 GHz band goes farther but is slower and is where all the neighborhood congestion lives. The 5 GHz band is faster and much less crowded but doesn't reach as far. If 5 GHz is fast up close but unusable across the house, that's a coverage limit. If 2.4 GHz crawls in the evening but is fine at 2 in the afternoon, that's neighborhood congestion.

Knowing how old your router is matters too. Log into the admin page (the address is usually on a sticker on the bottom of the router) and check the model number, then look up when it was released. Anything past about 2019 is borderline, and anything older than that is a strong candidate for replacement.

If it's time to replace it

A couple of things to look for when you're shopping, without getting into specific brands:

• Wi-Fi 6 at a minimum. Wi-Fi 6E or Wi-Fi 7 if your budget allows. These handle congestion much better than older routers, which directly fixes that evening-slowdown problem.
• A mesh system if your house is bigger than a couple of rooms. One router in one spot can only reach so far. A mesh setup gives you a couple of units that work together, and it fixes coverage problems that a single router never will. I use a wifi mesh in my house and it works great.
• Match the router to your plan, not the other way around. If you have a 300 Mbps plan, you don't need a router rated for multi-gigabit speeds. Pay for what you'll use.

Run through the test sequence first. Most of the time the answer will be obvious, and most of the time it has nothing to do with your ISP.