Decoding the URL Mystery: Load Testing Essentials

3 min readAug 21, 2023


Alright, let’s dive into one of the foundational pieces of load testing: the almighty URL. You know, that address you punch into your browser when you’re trying to visit your favorite website or access an API? But when it comes to load testing, not just any URL will do. There’s a bit of nuance here, and trust me, understanding this can save you some serious head-scratching moments.

LoadFocus Cloud Load Testing Tool

What Does the URL Field Accept?

When you’re all set to run a load test, one of the primary inputs you provide is the URL. This isn’t just any random website you’ve had bookmarked since 2008; this URL is the target. It’s what you’ll be testing.

Now, most testing tools are pretty chill and give you a straightforward field to pop that URL into. Something like:


Simple enough, right? Ah, but there’s a catch. It’s not just about what the field accepts, but what it can actually access.

Public vs. Local URLs: The Great Divide

Let’s clarify a couple of terms that can trip people up: public and local URLs. Think of them as the extroverted and introverted siblings of the internet world.

The Outgoing One: Public URLs

Public URLs are like those friends who always want to hang out at the most happening places in town — they’re accessible, available, and always up for some fun. In the web context, these are URLs accessible from anywhere on the internet. That means anyone with the link, anywhere in the world, can punch it into their browser and get to the website.

You know the kind:


These are the kinds of URLs load testing tools adore. They can reach out from wherever they’re located and send a ton of requests to see how well that website can handle traffic. It’s like checking how many people your favorite coffee shop can handle before the baristas start throwing lattes.

The Homebody: Local URLs

Then there are the local URLs, the more introverted types. These URLs are the cozy, stay-at-home-on-a-Friday-night kind. They typically refer to a device’s local environment or perhaps a private network. These are not party animals; they’re not out there on the global internet.

Some classic local URL examples are:arduinoCopy cod


Now, here’s the thing: load testing tools, being the outgoing party animals they are, can’t easily hang out with these introverted local URLs. They’re external and can’t access a private or local network, so they just end up standing outside the door, unable to join the party.

The Load Testing Nuances

Alright, let’s tie this back to our load testing scenario. When you’re gearing up for a load test and have to enter a URL, you need to remember the testing service’s perspective. If you provide a local URL like http://localhost, it's like sending your friend to a party that's happening in a dream. They simply won't be able to find it.

So, the golden rule? Stick to public URLs. They’re accessible, easy to test, and most importantly, you’ll get the results you’re looking for.

The Local Testing Workaround

“But wait,” you might ask, “what if I really want to test my local environment?” Well, there’s a workaround involving tunneling services that create a bridge between your local environment and the external world, but that’s a chat for another day.

Wrapping It Up

Understanding the difference between public and local URLs might seem like a tiny detail, but it’s essential for load testing. Making sure you’re using the right kind of URL ensures your tests run smoothly, and you get valuable insights to improve your web services.

LoadFocus offers a comprehensive load testing experience, and the right URL is the starting point to unlocking its full potential. By understanding the nuances of public and local URLs, you’re setting the stage for more effective, accurate testing. Here’s to stress-free websites and apps that can handle the pressure! And when in doubt, always remember: Public URL is the way to go with LoadFocus. Happy testing!