Yes, but neither can beat your plan
Both your modem and your router can affect the speed you see. Neither can make your connection faster than the plan you pay your internet provider for. If your gear is old or mismatched with your plan, it can hold you below that limit. If it is up to the job, upgrading it will not add speed.
What each device does
- Modem: connects your home to your provider’s network (cable, fiber terminal, DSL). It translates the signal your provider sends.
- Router: shares that connection with your devices, over Wi-Fi and Ethernet ports, and manages the local network.
- Gateway: a combined modem and router in one box, which many providers supply. See gateway vs router.
How a modem can limit speed
- Old standards. For cable internet, a DOCSIS 3.0 modem may struggle with higher plans, and DOCSIS 3.1 is generally recommended for faster tiers. Check the rated speed on the modem and your provider’s list of supported models.
- Slow ports. A modem or gateway with a 100 Mbps Ethernet port cannot deliver more than that over the cable.
- Wear and signal problems. A failing modem can drop connections or run slow. Warning signs include frequent disconnects and lights that keep changing. Your provider can check the signal levels.
How a router can limit speed
- Wi-Fi standard. Older Wi-Fi standards have lower real-world speeds. Our Wi-Fi router speeds chart explains the numbers.
- Slow ports or processor. Some older or budget routers cannot pass a gigabit connection at full speed, especially with features like QoS or VPN turned on.
- Placement and interference. Where the router sits has a large effect on Wi-Fi speed. See where to put your Wi-Fi router.
- Overload. Many busy devices can strain a weak router. See how many devices a router can handle.
A simple test to find the limit
- Run a speed test on a computer connected by Ethernet directly to the modem (if your provider allows it). Compare it to your plan. A result close to your plan, within normal variation, means the modem and line are probably fine.
- Connect the computer to the router by Ethernet and test again. A big drop suggests the router.
- Test on Wi-Fi next to the router. A further drop points to the Wi-Fi hardware or settings.
- Test on Wi-Fi in the slow room. A further drop points to range and interference.
Speed tests vary from one run to the next, so repeat each a couple of times and test at different times of day.
Is 500 Mbps fast?
For many homes, yes. 500 Mbps is generally enough for several people streaming, video calls and downloads at once. The more important question is whether your devices and Wi-Fi can actually use it. A single device often will not reach the full number over Wi-Fi.
Why is internet slow lately?
If speeds dropped without any change at home, the cause may be provider congestion, an outage, or a line fault. Check your provider’s status page and test directly at the modem. Also look for a new device downloading in the background.
When an upgrade is worth it
Replacing equipment may help if:
- Your modem is not rated for your plan speed.
- Your router’s ports or Wi-Fi are slower than your plan.
- The equipment is many years old and unreliable.
- Your provider says the model is no longer supported.
Check compatibility with your provider before buying a modem. For a router, look at the Wi-Fi standard, port speeds and the size of your home. An upgrade usually means installing the new device, logging in, setting a Wi-Fi name and password, and moving your devices over. Our guide to replacing your modem and router walks through it, and do you need a special router for fiber internet covers the fiber case.
If you own a Netgear and think it is the problem, see why a Netgear router slows down your internet. If you use more than one router, read do multiple routers affect speed.