Free performance, load, and stress test
for web servers
Webserver Stress Tool is a powerful HTTP-client/server test application designed to pinpoint
critical performance issues in your web site or web server that may prevent optimal experience
for your site's visitors.
By simulating the HTTP requests generated by hundreds or even thousands of simultaneous users, you can test your web server performance under normal and excessive loads to ensure that critical information and services are available at speeds your end-users expect.
Detailed test logs and several easy to read graphs make analyzing results a snap. Webserver Stress Tool for Windows (2003 R2, Vista, 7, 2008) can benchmark almost any HTTP server (e.g. static pages, JSPs/ASPs, or CGIs) for performance, load, and stress-tests.
Number of Users
Tested Web Server
DELL Optiplex 7010, one cpu, 4 cores, Intel Core i5-3550S @ 3 Ghz,
DELL R710 Server with two cpus, 24 cores, Intel Xeon X5650 @2.67 Ghz, 128 GB RAM, Windows 2008 R2 (running Webserver Stress Tool)
Comments: This test was run without downloading images.
Performance Test Samples and Screenshots
In our Sample Performance Tests section you can find a collection of test reports with detailed information about setup and results. This screenshot, for example, shows the spectrum of click times.
Why should you use Webserver Stress Tool?
Using Webserver Stress Tool when developing and running Websites is important for your web infrastructure:
- Maximize Uptime: Resolve performance critical issues in your webserver before they bring down your website
- Maximize Performance: Make sure that your websites and applications are given the server resources they need when they need it to guarantee a high quality user experience
- Maximize ROI: Get everything out of the investment in your webserver technology through consistent and in-depth testing and analysis
- Minimize Efforts: The software installs in 5 minutes and works with all web servers
- Read more about the features
How much load can Webserver Stress Tool generate?
We have successfully tested Webserver Stress Tool 8 with
- more than 500 Mbit/s network load
- more than 1,000,000 pageviews per hour and
- up to 10,000 simultaneous users
See our Sample Performance Tests section for detailed test reports. The actual load you can achieve is highly dependent on your network infrastructure, your server/client hardware, the file sizes, and your web application. We also provide screenshots of Webserver Stress Tool.
Webserver Stress Tool simulates lots of users by sending http-requests to a webserver. It works with almost any server based technology like asp, jsp, cfm, or java. Many different load patterns can be generated with this web testing tool.
The simplicity of Webserver Stress Tool means any webmaster, programmer, or administrator of a web site can test a webserver/web application under heavy load in real-time. This provides unparalleled ability to quickly adjust webserver configurations for optimal performance (i.e. when a new feature or content is launched).
After running the standard installer it takes a few minutes to configure and start a test. Several users reported to us that they found a long searched bug in their software within 15 minutes after downloading and installing Webserver Stress Tool.
On our case study page you can find several case studies for Webserver Stress Tool.
Webserver Stress Tool can simulate anything between 1 and 10,000 users. The maximum number of simultaneous users that can be simulated successfully depends on the power of the client machine Webserver Stress Tool runs on, as well as the Windows version used on that machine. E.g. we have tested up to 10,000 users on a Xeon 2.8 Ghz machine with hyperthreading on Windows XP. For details, please see System Requirements.
5-10 MB of disk space plus space for the log files (can be several MB) and about 100 kb of RAM per simulated user.
Why does Webserver Stress Tool show errors when I run it against my server? When I access the website with my browser I don't see errors.
In most cases when people write us about errors when using Webserver Stress Tool, they have discovered exactly what Webserver Stress Tool is designed to discover: Problems with scripts or webservers that crash or fail when multiple users access it simultaneously. You can be quite sure that you have a server problem if you get errors other than "timeout" and "404." For example, the error code 500 (internal server error) is never generated by Webserver Stress Tool, but by the webserver.
Here are some tips:
- Run the test with just one user, increase the number of users step by step. If that works with one or a few users without errors it is almost certain that your website has a problem with simultaneous users
- Enable Write Detailed and User Logs and Write Headers to Log and review the user logfiles for hints about the problem
- Enable Save All HTML files and review the resulting webpages
- Review the webserver's or the application's error log file