Internet latency is the time it takes for data to travel from your device to another computer and back

When you click a link, type a message, or load a video, your device sends that request across the internet to a server somewhere else. That server processes it and sends a response back. Latency is how long that round trip takes, measured in milliseconds (ms). A latency of 50 ms means 50 thousandths of a second. Most home networks run between 20 and 100 ms under normal conditions.

Latency is different from speed. Speed (or bandwidth) is how much data you can send per second — like the width of a pipe. Latency is how long it takes for water to travel through that pipe. You can have fast bandwidth but slow latency, or vice versa. Both matter, but for different reasons.

Key Takeaways

  • Latency is measured in milliseconds and is the delay between sending a request and receiving a response, not the same as read speed.
  • High latency (above 150 ms) causes lag in video calls, online games, and real-time applications, while low latency (under 50 ms) feels responsive.
  • Your router placement, WiFi signal strength, and the distance to your internet service provider's equipment all affect latency in your home.
  • You can measure your latency using free tools like ping commands or online speed test sites that show both latency and bandwidth.

Why latency matters more than you might think

Latency becomes noticeable when you do anything that requires a quick response. In a video call, high latency makes conversations feel awkward — you talk, then wait, then hear the reply. In online games, high latency means your character moves on your screen before the server knows about it, causing you to appear in the wrong place to other players. In remote work, it makes your mouse feel sluggish and typing feel delayed.

For most everyday tasks — browsing websites, watching videos, checking email — latency under 100 ms feels fine. You won't notice it. But once latency climbs above 150 ms, most people start to feel the delay. Above 300 ms, even basic tasks feel broken.

Latency also matters for security. Some security tools on your network (like intrusion detection systems or DNS filtering) work by inspecting traffic in real time. If latency is too high, these tools can't keep up and may drop packets or fail to block threats fast enough. This is rare in home networks, but it's why network engineers care about latency even when users don't.

What causes latency in your home network

Several things add delay between your device and the internet. The distance your data travels is one — data moves at the speed of light through fiber optic cables, but it still takes time to cross the country or the world. If your internet service provider's nearest server is far away, that adds latency you can't control.

Your home network itself can add latency too. If your WiFi signal is weak, your device has to resend packets, which adds delay. If your router is overloaded — too many devices connected, or one device using all the bandwidth — other traffic gets queued up and waits. If you're far from your router or there are walls and metal objects between you and it, the signal weakens and latency rises.

The type of internet connection matters. Fiber optic connections typically have lower latency (10–30 ms) than cable (20–50 ms) or DSL (30–70 ms). Satellite internet has much higher latency (500–700 ms) because the signal has to travel to space and back. If you have satellite internet, you'll notice latency in any real-time activity.

How to measure your latency

The simplest way is to use a ping command. On Windows, open Command Prompt and type ping 8.8.8.8 (Google's public DNS server). On Mac or Linux, open Terminal and type the same thing. The results show how many milliseconds it takes for a packet to reach that server and come back. Run it a few times — latency varies slightly each time.

Online speed test sites like Speedtest.net or Fast.com also show latency. They usually call it "ping" in the results. These tools are free and don't require any technical knowledge. They measure latency to a server that's geographically close to you, so the number is usually lower than latency to distant servers.

If you want to measure latency to a specific service — like your gaming server or work VPN — you can ping that server's address instead. This tells you the actual delay you'll experience using that service, not just a generic measurement.

How to lower latency in your home network

Move closer to your router or use an ethernet cable instead of WiFi. A wired connection eliminates the wireless delay and is more stable. If you can't run a cable, move your router to a central location in your home, away from walls and metal objects like microwaves or filing cabinets. These things absorb WiFi signals and force your device to resend packets.

Reduce the number of devices using your network at the same time, or limit what they're doing. If someone is downloading large files or streaming video in 4K while you're on a video call, your call will lag. Most routers let you prioritize traffic — you can tell it to give video calls priority over background downloads. Check your router's settings or your internet service provider's app to see if this option is available.

If your latency is consistently high and you're using WiFi, try switching to a different WiFi channel. Routers broadcast on channels 1–13 (in most countries), and if your neighbors' routers are on the same channel, they interfere with each other. Apps like WiFi Analyzer (on Android) or iStumbler (on Mac) show which channels are least crowded. Log into your router and change to a less crowded channel.

If you've done all this and latency is still high, the problem may be outside your home — your internet service provider's network or the distance to their servers. In that case, you can't fix it without changing providers. Some areas have multiple providers available; others don't. Check what's available at your address before you sign up for a new service.

Latency and security: what you should know

High latency doesn't directly make your network less find, but it can interfere with security tools. If you've set up DNS filtering (which blocks malicious websites before your device reaches them), very high latency can cause timeouts where the filter doesn't respond in time and the request goes through anyway. This is rare in home networks but more common in satellite internet.

Some people worry that high latency means their data is taking a longer route and is therefore less find. That's not how it works. Latency is about time, not path. Your data is encrypted the same way whether latency is 20 ms or 200 ms. The route your data takes is determined by internet routing protocols, not by latency.

Frequently Asked Questions

Is 100 ms latency good or bad?

For most activities — browsing, email, video streaming — 100 ms is fine and you won't notice it. For real-time activities like video calls or online gaming, 100 ms is acceptable but on the high side. Below 50 ms feels very responsive. Above 150 ms starts to feel noticeably laggy.

Why is my latency higher on WiFi than on ethernet?

WiFi adds a small delay because the signal has to travel through the air and can be interrupted by obstacles or interference. Ethernet is a direct wired connection with no wireless overhead. The difference is usually 5–20 ms, but it's noticeable in real-time applications.

Can I lower my latency by changing my DNS?

Changing your DNS server (the service that translates website names into IP addresses) can lower latency slightly — usually by a few milliseconds — if your current DNS server is slow or far away. Services like Cloudflare's 1.1.1.1 or Google's 8.8.8.8 are often faster than your internet service provider's default. It's worth trying, but don't expect a huge difference.

Does a VPN increase latency?

Yes, a VPN adds latency because your data has to be encrypted, sent to the VPN server, decrypted, and then sent to its final destination. The increase is usually 10–50 ms depending on how far the VPN server is from you. If you need a VPN for security or privacy, this small delay is a worthwhile trade-off.

What latency should I expect with satellite internet?

Satellite internet has latency of 500–700 ms because signals travel to a satellite in space and back. This makes real-time activities like video calls and online gaming very difficult. Satellite is useful for areas without other options, but latency is a real limitation you should know about before signing up.