Because, like, electricity travels at the speed of light, right? If you can make a phone call anywhere in the world instantly, how come your speed test results are so different if you test from different areas? That doesn’t make sense, does it?
Light doesn’t always travel at the same speed. Really.
First of all, let’s get this out in the open right now: electricity travels at the speed of light but the speed of light isn’t always the same. You know that number you learned in school… 186,000 miles per second? That’s the speed of light in a vacuum. When you’re talking about speed over a piece of fiber optic cable or copper wire the number is quite differently. Most web sites will punt at this point and tell you the number varies wildly but if you add up all the fuzzy math it looks like most sites get to about 15,000 miles per second which is a lot slower than that number you learned in school. So yeah, that’s a part of it.
It’s not really about the speed of light anyway.
The bigger part, though, is something you’re very familiar with if you live near a major city: congestion. Every time your data goes out in the world, it’s making a trip filled with intersections, virtual stoplights, slow onramps, all the stuff you urban dwellers know so well. Those branches on the internet may happen really, really quickly but add up enough of them and they’re going to slow things down.
Remember too that sometimes the major “pipes” that make up the internet can get overloaded, and the “interconnects” that connect the whole internet to your internet service provider aren’t infinite. Netflix subscribers nationwide are well aware that sometimes, things bog down.
So, if you’re into internet bragging rights, make sure you test the closest possible server. On the other hand, if you’re curious about how well you’re actually going to get to somewhere on the internet, test your speed to some of the major data centers in this country: Denver, central Kansas, San Antonio, etc. If you’re curious about where your favorite web site is physically located, you can use a tool like IPLocation to get an idea, then do a speed test to that general location. It will give you a much better idea of the real speed you’re going to get once you get done staring at those essentially false speed test results.
How much speed is important anyway?
The real question is, are you testing the speed of your internet for bragging rights, or for something else? Most servers on the internet can’t actually send you out anything faster than about 10 megabits per second. That’s right, 10. That seems really slow, right? Video servers and content streaming sites can generally get up to about 25, but then why would you pay for faster internet than that?
There’s a lot more to it than raw speed.
Your internet speed is actually your internet capacity. If you’re one person with one device, then you could get maximum speed, if anyone could serve something to you that fast. But who has one device anymore?
If you have a 100 megabit per second line, that’s the maximum speed that everyone in your home will get, combined. Your kids will both stream video at 10 megabits per second, you might be updating your devices, someone else could be playing an online game or shopping, and then one of your friends or relatives could be updating their social media. Together, the demand on your internet line can be bigger than you expect. It’s even more complex when you’re web browsing since you can have 100 different web connections at the same time and not even know it. The ads may come from one server, the pictures from another, the words from a third, and the video from somewhere else. The more internet capacity you have, the smoother it’s all going to seem.