Posted by the editor on December 07th, 2009

If you just bought a shared web hosting account, a VPS (Virtual Private Server) or a dedicated server and set up your domains and sites, you might wonder just how much traffic they can take on. After all, you don’t want your site to go down when there is a spike of a few thousand visitors per minute from Digg or other social networks. This would look very bad and you can miss on a lot of income, if that was your goal.

I’m going to show you a perfect solution, a service which will simulate hits to your site so you can see just how many simultaneous connections/visitors can your site handle. Probably the best part is that it is free (with a catch, of course).

This is the only such service that I know of, and this is surprising, as there are a lot of webmasters who would want something like it. The service has been very successful since its launch and I think we will start seeing more of these appearing in the near future.

Anyway, until now, if you wanted to stress test your site or server, you had to have another dedicated server (simple webhosting and VPS may not be enough for this), where you would install special software (which also costs money) that would simulate visitors coming to your site. This was quite hard to setup for an average webmaster (not to mention it was expensive).

So how is this wonder service called and where can one find it? I present you loadimpact.com . If you visit the site, you’ll see it is very intuitive and easy to use. The free version allows you to simulate up to 50 simultaneous users (or users per second), which I found to be more than enough for stress testing any shared web hosting accounts and cheap VPS servers with 256-512 MB RAM.

You can run only 1-2 tests (depends on the size of your home page) without registering, but if you register (it’s free), you can run 4 guaranteed free tests. This was done to prevent anyone from overloading your server using their service (also called a Denial of Service attack).

If you have a dedicated server and want to see its full potential or any unforeseen problems that may appear under heavy load, you can buy a paid subscription (the basic 9$/day should be enough for most small single dedicated servers with 2-4 cores and 2-4 GB RAM, while the professional and advanced subscriptions can be used to measure the performance of a whole cluster, used on big sites like amazon.com, for example).

To start the tests just enter your domain name or IP address and click “Start Test”. You can actually stress test individual pages by entering their location (like www.mysite.com/shopping-cart.html), which is useful if you have a big site with a lot of features (like a forum, blog, shopping cart, etc.) and want to test them individually.

This is it, now you have a great site/server stress testing tool, which you can easily use anytime. Be sure to check out and bookmark it at loadimpact.com