Latency is the delay that occurs between an action and the response to that action in a system. In technical terms, latency usually refers to the time it takes for a data packet to travel from one point to another. The lower the latency, the faster the system's response.
For example, when you click on a link to open a website, the time between your click and the page actually loading is partly determined by latency. The same delay plays a role in online gaming, video calls, streaming, and other real-time applications.
Latency is typically measured in milliseconds (ms). It may seem minor, but even a few milliseconds can be noticeable in certain situations. Low latency is especially important for applications that require immediate feedback, such as remote control systems, VoIP, and trading platforms.
Latency occurs across many technological environments. While the core idea remains the same, a delay between cause and effect, the impact and meaning can vary depending on the context. Below is an overview of the most common applications.
In networking, latency refers to the time it takes for a data packet to travel from one computer to another across a network connection. The faster this happens, the smoother the experience. High latency can result in slow-loading websites, stuttering video streams, or lag in online games.
In live audio or video transmissions, latency can cause communication delays. Think of a video call where the other person responds half a second after you speak. In music production, low latency is essential, ensuring that recorded sounds are played back instantly and without delay.
In computing, latency refers to the response time between components for example, how long it takes a processor to access memory or storage. Fast SSDs, for instance, have much lower latency than traditional hard drives, leading to quicker load times and better performance.
In technical simulations, such as those used in aviation or automotive industries, low latency is crucial for realism. When a pilot presses a button in a flight simulator, the system needs to react instantly to maintain a true-to-life experience. Similarly, robotics and mechanical control systems rely on low latency for precision and accuracy.
Latency is caused by a combination of factors. It's rarely due to a single issue. In networking, software, and hardware, multiple components work together to determine the total delay. Below are the most common causes.
The farther data has to travel, the higher the latency. Data moves through cables or via satellites and often passes through multiple network nodes. Even at the speed of light, covering long distances takes time. This is especially noticeable with satellite connections.
Outdated routers, switches, processors, or storage devices can introduce delay. When hardware struggles to process data quickly or respond to requests efficiently, overall latency increases. This applies to both networking equipment and end-user devices.
Heavy network usage can lead to congestion. Just like in road traffic, this causes delays. Data packets may be queued or retransmitted, raising latency. This is common during peak hours or on heavily visited websites.
Not all internet connections are equal. Fiber-optic connections generally offer the lowest latency due to their high speed and direct transmission. Satellite internet has the highest latency because of the long distances signals must travel. Copper-based lines like DSL fall somewhere in between.
Sometimes data doesn’t take the shortest or fastest path. Internet traffic passes through routers that determine how packets are routed. The protocol used (such as TCP or UDP) also affects latency TCP, for example, includes error checking and retransmissions, which can slow down the connection.
Latency is not the same as bandwidth or throughput, although these terms are often confused. Each describes a different aspect of network performance, and together they determine the overall user experience. Below is a clear explanation of the differences and how they relate.
Latency refers to the delay between sending and receiving data. It’s usually measured in milliseconds (ms).
Bandwidth is the maximum amount of data that can be transmitted over a connection, measured in Mbps or Gbps.
Throughput is the actual amount of data successfully transmitted in a given time period, which is often lower than the theoretical bandwidth.
So, a network can have high bandwidth but still feel slow if the latency is high. Think of it like a highway (bandwidth) filled with cars that accelerate slowly (latency).
Latency primarily affects the responsiveness of a connection. Bandwidth determines how much data can be sent at once. If you're downloading a large video file, bandwidth is key. But if you're in a video call, low latency is crucial for smooth communication.
In practice, these factors work together. An internet connection only feels fast when both latency is low and throughput is high. This means faster loading websites, fewer video buffering issues, and instant responses during gaming or voice calls.
Latency has a direct impact on the speed and smoothness of digital experiences. In many cases, delays only become noticeable when latency is high. However, even at low levels, it plays a significant role, especially in real-time applications. Below are several key areas where latency truly matters.
Websites and apps with high latency respond slowly. Pages load sluggishly, and interactions feel unresponsive. In e-commerce or web-based platforms, this can lead to user frustration, higher bounce rates, and lost revenue. Even milliseconds can make a difference in conversion rates.
In online gaming, every millisecond counts. High latency results in input lag, stuttering visuals, or disconnections. Similarly, during video calls or live streams, high latency causes noticeable delays, leading to awkward interruptions and broken conversations.
Speed is everything in finance. Latency determines how quickly a stock order is executed. In this environment, milliseconds can be worth millions. That's why banks and trading firms invest heavily in ultra-low latency infrastructure to gain even the smallest advantage.
In the world of IoT (Internet of Things), smart factories, and automation, latency is critical for precision and safety. A robotic arm that reacts a few milliseconds too late can make mistakes or cause damage. The same goes for autonomous vehicles, where latency affects how quickly the system can respond to traffic situations.
As a website owner, you have control over much of the latency that visitors experience. With the right technical optimizations, you can ensure your site responds faster and delivers a smoother experience. Below are practical steps you can take.
Large images, videos, and unnecessary scripts can slow down your website. By compressing images, hosting videos externally, and removing redundant scripts, you reduce the amount of data that needs to be transferred. This lowers the total load time and improves perceived latency.
A Content Delivery Network (CDN) distributes your website’s files across multiple servers worldwide. Users then load your site from a server that is physically closer to them. This shortens the distance data has to travel and significantly reduces latency.
Cheap hosting often means shared servers with high traffic, which can lead to higher latency. Invest in a reliable hosting provider with modern infrastructure, solid uptime, and high-performance servers. This not only improves your site’s speed but also its stability.
Tracking pixels, widgets, fonts, and ads from third parties can introduce delays. Each external request is an extra connection that may respond slowly. Keep external scripts to a minimum and load them asynchronously where possible to avoid blocking your site’s performance.
As an end user, you can also influence latency. Especially when gaming, video calling, or using real-time applications, it's useful to know how to reduce delays. Below are some practical tips.
A wired connection is generally faster and more stable than Wi-Fi. Wireless signals can be disrupted by walls, other devices, or distance from the router. Ethernet avoids these variables and results in lower and more consistent latency.
An outdated router or modem can slow things down. Newer models support faster protocols like Wi-Fi 6 and handle multiple connections more efficiently. Your laptop or PC can also affect latency if the network card or drivers are outdated.
Your internet provider’s default DNS server isn't always the quickest. Switching to a public DNS like Cloudflare (1.1.1.1) or Google (8.8.8.8) can speed up how fast domain names are resolved, which helps websites load faster and reduces perceived latency.
When multiple devices or users are consuming a lot of bandwidth, such as streaming or downloading large files, network congestion can increase latency. Close unused apps or pause large downloads during gaming, video calls, or remote work sessions.
To understand and improve latency, you first need to know how to measure it. There are several tools and methods available to make network or system delays visible. Below we explain how this works and what qualifies as good latency.
One of the most well-known ways to measure latency is by using the ping command. It sends a small data packet to a server and measures how long it takes to receive a response. The result is shown in milliseconds (ms).
Other popular tools include:
Traceroute: shows the path a data packet takes and how much delay each node causes.
Speedtest.net: measures latency alongside your upload and download speeds.
PingPlotter: an advanced tool that visualizes network issues and latency over time.
Monitoring tools like Datadog or New Relic: useful for websites and applications that need continuous insight into latency.
What’s considered “good” depends on the use case. Here’s a general overview:
In general, the lower the latency, the better. Stability is also important, connections with low but highly variable latency (known as jitter) are often less reliable than slightly higher but consistent values.
Latency is often misunderstood. Many people confuse it with other networking terms or draw the wrong conclusions about speed. Below are some of the most common misconceptions explained.
These two terms are often used interchangeably, but they’re not the same.
Latency is a measurable delay between an action and the system’s response.
Lag is the visible effect of high latency or unstable connections, such as stuttering, delay, or freezing.
You can have low latency without lag, and you can experience lag even if latency is low, due to issues like packet loss or hardware limitations.
Not necessarily. Bandwidth refers to how much data can be sent at once, while latency refers to how quickly the first packet of data arrives. It’s possible to have a high-bandwidth connection with high latency, especially if the physical distance is large or the network is poorly managed.
A faster internet connection (more Mbps) is useful for downloading large files or streaming in high quality, but it doesn’t automatically reduce latency. For example, switching from 100 to 500 Mbps won’t lower latency if your router or DNS server responds slowly. For real-time applications, quick responsiveness is more important than raw download speed.
Latency plays a silent but crucial role in our digital experiences. Whether it's websites that need to respond instantly, smooth video calls, real-time gaming, or industrial automation, low latency makes the difference between seamless and frustrating.
By understanding what latency is, what causes it, and how you can reduce it, both users and website administrators can make better decisions. From hardware to hosting, from Wi-Fi to DNS: every component matters. And in a world where speed is increasingly important, latency is no longer a side issue, it's a key concept.
Latency is the delay between the moment a signal is sent and the moment it is received. In networking, it refers to how long data takes to travel from point A to point B.
Yes, high latency results in slower responses from websites, apps, or games. It can lead to delays, lag, or a poor user experience.
Latency is the measurable delay in milliseconds. Lag is the visible effect of high latency, such as stuttering in games or delays during a video call.
For most activities, anything under 100 ms is considered good. For online gaming or financial systems, latency under 30 ms, or even 10 ms, is ideal.
