Networking

Modem vs Router: What's the Difference?

Updated 2026 · 5 min read

People use "modem" and "router" interchangeably, but they're two different devices with different jobs. Understanding the difference helps you troubleshoot slow internet.

How internet reaches your devices1Internet2Modem3Router4Your devices
The path your connection takes: the modem brings the internet in, the router shares it out.

What a modem does

The modem connects your home to your ISP. It translates the signal coming over the cable, fibre or phone line into data your devices can use. One job, one connection.

What a router does

The router takes that single internet connection and shares it with all your devices — over WiFi and Ethernet — and manages traffic between them. Your WiFi network is created by the router, not the modem.

Why you often have both (or a combo)

Many ISPs provide a single "gateway" box that's a modem and router combined. Separate devices give more control and often better WiFi, but a combo unit is simpler.

Key takeaway: Slow speeds on every device often point to the modem or your plan; slow speeds only on WiFi (while wired is fine) point to the router.

How they affect speed

An old modem can cap your speed or cause bufferbloat; an old or poorly placed router limits WiFi range and multi-device performance. Run our test wired (tests the modem/line) and on WiFi (tests the router) to find which one is holding you back.

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