Compatibility comes before speed
Find your provider's requirements for using a separate router. The incoming service may need particular settings or additional equipment, and telephone services may depend on the supplied box. A matching Ethernet socket is not enough to establish that a new router can replace everything in the current installation.
Write down the intended arrangement before shopping. Will the new unit route the connection, act as an access point or join a compatible mesh system? Those roles affect which features matter and which ports are used. Confirm the supported mode in the exact model's documentation.
Separate the different speed claims
A wireless class number is not a promise that one device will download at that speed. It may describe combined theoretical capabilities across bands. Your usable result also depends on the client device, distance, interference, port speeds and the incoming broadband service.
Look at the WAN and LAN ports individually. If you need a particular wired transfer rate, every relevant port, cable and adapter in that path must support it. A fast wireless label does not remove a slower wired link elsewhere. Likewise, buying a newer wireless generation does not give an older laptop capabilities it does not have.
Read the features you will actually use
Guest networking, supported mesh expansion, parental controls and traffic management can be useful, but their details differ. Check what each feature does rather than relying on a tick in a comparison table. Some advanced options may require an account or subscription; include that in the decision.
Find the update and support information. A router sits at an important point in the household connection, so ongoing maintenance matters alongside hardware. Check the exact product and hardware revision where the manufacturer distinguishes them.
Leave room for the physical box
Measure the place where it will sit and inspect cable access. A router that only fits inside a crowded cupboard may create a placement problem immediately. Check ventilation guidance, power requirements and whether the lights can be adjusted if the unit will be in a bedroom or living room.
Choose around a specific improvement: better coverage with suitable placement, additional wired ports or a supported feature you need. Keep a short list of those requirements and ignore specifications that do not change your intended use. That makes the comparison clearer and reduces the chance of paying for a number that never becomes a noticeable benefit.
