At we commonly get asked, “Why is my internet so slow?” Many factors can contribute to a slow internet connection. The first step to diagnosing your particular issue is understanding that “slow” can mean two very different things.
  1. Slow internet can be caused by low bandwidth.
  2. Slow internet can be caused by high latency.
There can also be slowdowns caused by things like Wi-Fi signal interference and over-loaded routers, but if all your equipment is working properly, then latency and bandwidth are the two likely culprits of your slow internet. First, find out how much speed you actually need in your household by clicking the tool below. speedtool-hsi

What is bandwidth?

Bandwidth is what almost all internet service providers call “speed” in commercials and marketing. That can be a little misleading, because high bandwidth will not always result in an internet connection that feels fast to you. Bandwidth is measured in Mbps or megabits per second. Your internet connection will have two bandwidth numbers: download speed, and upload speed. Most ISPs only talk about download speed, because download speed matters most to most people. Unless you’re sending files, upload speed matters less.

What is Latency?

Latency is the delay between when you click something and when you see it. It’s the time it takes for your request for data to get to a server (like a website), and then for the data to get back to you. Latency is measured in milliseconds, abbreviated “ms”. Most people will begin to notice delays of about 150-200ms. “Ping” is another word that is often used interchangeably with latency.  “What’s your ping?” is another way of asking, “What is your delay/latency (in ms) to the server?”  

So what’s the difference between bandwidth and latency?

It’s easiest to explain the impact of each in some hypothetical scenarios:
  • If your bandwidth is good and your latency is bad: Web pages would take a long time to start loading, but once the initial connection was made the rest of the page would load almost instantly.
  • If your latency is good and your bandwidth is bad: Web pages would begin to load almost instantly, but the page would load slowly, one piece at a time.
Again, “good bandwidth” means bigger numbers, measured in Mbps. “Good latency” means a low response time, also called ping, which is measure in ms.
Think of your internet like a water pipe, where you’re sending water out through one pipe and bringing it in through another. Bandwidth is like the size of the pipe and the volume of water it can send or receive at any point. Latency is like water pressure; it’s the speed at which water goes through the pipe.  

Why does latency vs. bandwidth matter?

Gaming actually doesn’t need “fast” internet in the sense that it’s usually marketed. Bandwidth is relatively unimportant (except for getting game patches faster), but latency is key. Low ping times are highly-prized in fast-clicking twitch games like Call of Duty or Battlefield.

Streaming video or audio is mostly a matter of bandwidth, but latency can also cause problems. In theory a high-bandwidth connection with high latency would work, but in practice it rarely does. Most streaming services aren’t equipped to buffer long enough to stream seamlessly, even with a major buffering wait at the beginning. There are apps like NightShift that pre-load streaming content for high-latency users, but at that point you’re essentially downloading videos and not streaming at all.

Video chat works best with low latency. It will still work with high latency, but you’ll have to work with the awkward delay in the conversation. HD video streaming will require more bandwidth, but the blurry sort of chat most of us are used to will only require a couple Mbps.

Browsing works best with decent latency. While you can get by with high latency, it can be frustrating that you have to wait several seconds every time you visit a new page. More bandwidth doesn’t hurt, either, especially if you’re looking at high-res images, gifs, or video.


Which services have good bandwidth, and which have good latency?

Most wired connections have fairly low latency. DSL and cable generally have 10-30ms response times within the US. Fiber is slightly faster at 5-20ms depending on equipment and location. Unfortunately, there is no way to know what your latency is going to be before purchasing, but generally it will be acceptable on wired connections. Satellite internet is notorious for high latency. Many games are difficult or impossible to play on satellite internet, because the signal must literally go to space and back. The majority of the delay is in processing and re-transmitting the signal. We don’t generally recommend satellite Internet due to bandwidth concerns when a wireline connection is available.
Technology Example providers Average DL speed Average latency Providers
Cable XFINITY by Comcast, Charter Spectrum, Cox Comunnications 41 Mbps 28ms See cable providers
DSL AT&T, Frontier, CenturyLink 16 Mbps 44ms See DSL providers
Fiber AT&T, Frontier, CenturyLink 73 Mbps 17ms See fiber providers
Satellite Hughesnet 7 Mbps 603ms See satellite providers
Of course your actual speeds and latency will depend on which providers are available in your area. If you need help determining which internet providers are available near you, enter your zip code below:
<< More Frequently Asked Questions   A new report from Sandvine, a Canadian online analytics company, claims that streaming video now accounts for more than 50 percent of all North American bandwidth. Although we’ve known for some time that streaming video takes up a tremendous amount of bandwidth, knowing that it makes up a majority of that bandwidth is still pretty amazing. Netflix Reigns Supreme The streaming king (Netflix) is responsible for 36.5 percent of North American bandwidth on its own. Its 41 million streaming subscribers each watch an average of 93 minutes of content per day. That’s 3,813,000,000 minutes of video—7,254 years—of video streamed every day on one streaming service. Netflix passed 20 percent of U.S. bandwidth in 2010, and while comparing U.S. to North American bandwidth isn’t exactly apples to apples, such a rapid increase isn’t something worth splitting hairs over. YouTube takes up another 15.5 percent of North American bandwidth, and were it not for Netflix, that would be an incredibly impressive figure. According to YouTube, it has far more users than Netflix — more than a billion. These users collectively view hundreds of millions of hours of content each day, but the site doesn’t break that figure down by country or region. It doesn’t take much math to notice that each viewer watches less content than the average Netflix viewer, but that’s still a lot of cat videos. Amazon Video and Hulu each account for just under 2 percent of bandwidth each. And while HBO GO and HBO Now aren’t big bandwidth players yet, it’s interesting to note that on one network, on one Sunday night, 4.1 percent of all bandwidth was devoted to “Game of Thrones.” What’s Driving the Increase Streaming video’s percentage of online bandwidth is likely to increase even more in the next few years. The trend is being driven by several factors. • Increases in streaming video quality, and thus file size • Additional video content, as entertainment studios produce new digital content and digitize older content • New streaming providers, including PlayStation Vue, HBO Now, and Showtime’s upcoming streaming service • Faster Internet connections that make HD video more practical • Cord cutting and dissatisfaction with the current pay TV model • The ubiquitous presence of video cameras in smartphones, and easy ways to upload personal video content to the web • Increased adoption of TVs and gaming consoles designed to accommodate online streaming • Apps that allow pay TV subscribers to view TV programming on mobile devices Is This a Problem? The trend is so strong that networking hardware giant Cisco Systems predicts that by 2019, video streaming will take up 80 percent of online bandwidth worldwide, and 85 percent of the bandwidth in the U.S. Cisco predicts total worldwide Internet traffic at that time to be 2 Zettabytes, meaning that streaming video will take up 160 trillion gigabytes of bandwidth. Blog_Piechart_DLusage At that rate, it’s not crazy to think that increases in streaming video could begin to outstrip infrastructure and bandwidth improvements. In Britain, lack of infrastructure improvements mean that bandwidth rationing could someday be a real problem. We haven’t seen any such problems on a large scale, but streaming bandwidth demands have already led to smaller scale network problems. In Connecticut, administrators for the state government’s network blocked access to streaming video and audio sites after they discovered these sites were taking up 7 percent of the network’s available bandwidth. That was sufficient to slow consumer-facing government websites and applications. The effect on state government productivity—and resulting image problems—may have also been a factor. What Are You Watching? How much of this massive amount of bandwidth are you using? At this point, missing out on HD streaming video because your connection is too slow, lagging, or is unreliable for an enjoyable viewing experience is unacceptable. Even modestly-priced plans can now handle this level of bandwidth requirement for a single viewer, and better plans can let your whole family use the web on separate devices at the same time. If your plan can’t do that, it’s time to find a new provider or plan that can. [zipfinder]
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