The Simple Definition
Latency is the time it takes for a piece of data to travel from your device to a server and return. It is measured in milliseconds (ms) and is commonly called ping. When you click a link, send a message, or press a button in a game, your device sends a request across the network. The time until that request reaches the server and the response gets back to you is your latency.
A speed test measures latency by sending a small packet to a test server and timing how long the round trip takes. If it takes 35 milliseconds, your latency is 35ms.
Latency vs. Bandwidth: Not the Same Thing
People often confuse latency with internet speed, but they measure very different things. Bandwidth (download and upload speed) is how much data your connection can move per second. Latency is how long it takes for any single piece of data to make the trip.
Think of it like a highway. Bandwidth is how many lanes the road has — more lanes means more traffic can move simultaneously. Latency is how long it takes to drive from one end to the other. You can have a ten-lane highway that still takes 45 minutes to cross. A gigabit internet connection can still have 80ms of latency if the route to the server is long.
For activities that move large amounts of data — downloading files, streaming video — bandwidth matters most. For real-time applications like gaming, video calls, and remote desktop, latency matters more.
What Causes High Latency
Several factors add to your total latency:
Distance to the server: Data travels at roughly the speed of light through fiber optic cables, but that still means distance adds up. Connecting to a server on another continent adds tens of milliseconds just from physical distance.
Network hops: Your data doesn't travel in a straight line — it passes through multiple routers and switches between your home and the destination. Each hop adds a small delay, and a congested hop can add significantly more.
Wi-Fi overhead: Wireless connections add 5–20ms of latency compared to wired, plus they introduce jitter from interference. Every retransmission adds more delay.
Local network congestion: When multiple devices are actively downloading or uploading, your router's queue fills up and packets wait before being sent. This is called bufferbloat and can add significant latency during busy household traffic.
ISP congestion: At peak hours, the shared infrastructure between your home and the broader internet fills up. This is why evening latency is often worse than midday latency on the same connection.
Good vs. Bad Latency for Different Uses
| Use Case | Good Latency | Acceptable | Starts to Hurt |
|---|---|---|---|
| Competitive online gaming | Under 20ms | 20–50ms | Above 80ms |
| Video calls (Zoom, Teams) | Under 30ms | 30–80ms | Above 150ms |
| General web browsing | Under 50ms | 50–150ms | Above 300ms |
| Video streaming | Under 100ms | 100–300ms | Above 500ms |
| File downloads | Not relevant | Not relevant | Not relevant |
How to Measure Your Latency
The easiest way is to run a speed test. A good speed test reports ping alongside download and upload speeds. Run it from the device you actually use, on the same connection type (wired or Wi-Fi), at the time of day when you normally experience problems.
For a more detailed picture, you can use the ping command in your terminal. On Windows: ping -n 50 google.com. On Mac or Linux: ping -c 50 google.com. This sends 50 packets and shows you the minimum, average, and maximum latency — and how much it varies between packets.
How to Reduce Latency
The most impactful steps, roughly in order of effect:
- Use Ethernet instead of Wi-Fi. This eliminates the Wi-Fi overhead and removes wireless jitter entirely.
- Connect to a closer server. In games and other configurable apps, always choose the server region nearest to you geographically.
- Enable QoS on your router. This prevents large downloads from flooding the queue and adding latency to your real-time traffic.
- Restart your modem and router. Memory-related slowdowns in older hardware can add latency over time. A reboot clears them.
- Upgrade your router if it is old. Routers from several years ago may add 10–30ms of processing delay compared to modern hardware.
If your latency is high even on a wired connection with no other household traffic, the issue is likely between your modem and your ISP. Contact your provider with evidence — multiple speed test results at different times of day, showing the latency values.
Frequently Asked Questions
What is a good latency for internet use?
Under 20ms is excellent for gaming and video calls. Under 50ms is comfortable for most uses. Above 100ms starts to feel sluggish in real-time applications, and above 200ms is noticeably poor.
What is the difference between latency and bandwidth?
Bandwidth is how much data your connection can transfer per second. Latency is how long a single piece of data takes to make the round trip. You can have high bandwidth and still have high latency — they are independent measurements.
Why is my latency high even though my download speed is fast?
Download speed and latency measure different things. High latency is usually caused by distance to the server, too many network hops, Wi-Fi interference, or ISP congestion — none of which are fixed by buying a faster plan.
Does Wi-Fi increase latency?
Yes. Wi-Fi adds 5–20ms of overhead compared to a wired connection, and it introduces jitter from interference. For latency-sensitive uses like gaming or video calls, Ethernet gives noticeably better results.
How do I measure my latency?
Run a speed test at speedtesthq.com — it shows your ping alongside download and upload speeds. You can also use the ping command in your terminal to test latency to a specific server.
Can I reduce latency without changing my internet plan?
Yes. Switching to Ethernet, connecting to a closer server, enabling QoS on your router, and reducing background traffic can all lower latency without upgrading your plan.