Record test scripts using your favorite web browser. Simulate realistic user behavior on your website, web app, or API.


Customize your test scripts with Loadster's easy and intuitive script editor. No programming required -- but you can if you want to!


Play your scripts with hundreds or thousands of simulated users. Instantly generate detailed test reports to see how your site performs.

Cloud testing, or on-premises? You can have both.

Loadster Cloud provides on-demand load testing from our 10 cloud regions all over the world. Launch huge, cost-effective load tests in minutes!

Loadster Engine runs on your own servers, laptop, or workstation. Load test your private, in-house applications just as easily as public websites.

Loadster's scripts work exactly the same, whether you choose to test from Loadster Cloud or your own infrastructure.

You can even combine cloud and local engines in the same test! Get started for free

Load testing for the modern web

Loadster is a full-featured load testing solution for websites, web apps, and web services. It's built for real web apps and effortlessly handles cookies, user sessions, custom headers, dynamic form data and more. Loadster simulates individual user state and gathers stats for each virtual user separately.

Avoid crashes and downtime

Load test your web apps to know ahead of time that your app can handle hundreds or thousands of concurrent users. Avoid expensive crashes, slowness and downtime by simulating peak traffic conditions, so you can find the breaking point before your real users are ever impacted.

Test from both sides of the firewall

Generate load from your own hardware, or Loadster Cloud's on-demand cloud engines running on 5 continents. Loadster is a desktop/cloud hybrid solution for the best of both worlds. It works equally well on private networks and the public Internet.

Get up to speed quickly

Save time and money! You'll be running your first tests in minutes. Loadster's script editor is intuitive and easy to learn, while still offering advanced features for power testers. Save hours a day on data crunching, reporting, and the other not-so-fun aspects of load testing.

Run unlimited free load tests up to 25 concurrent users from your own workstation, plus get 100 units of Cloud Fuel for on-demand cloud testing, just for signing up! Questions?