Your site has a breaking point.

Let's find it before your users do.

Don't crash under peak traffic! Load test your web application with thousands of bots to optimize performance, control costs, and prevent downtime.

Start testing for free

Automate real Chrome browsers

or multithreaded HTTP clients

Browser Bot

Browser Bots control real headless Chrome browsers, for the most realistic load testing possible. Automating thousands of real browsers is the best way to stress test dynamic web apps and modern websites.

Best For
Web Applications, Modern Websites
Fuel Consumption
Loadster Fuel Loadster Fuel Loadster Fuel Loadster Fuel
Protocol Bot

Protocol Bots execute scripted HTTP/S requests against your website or API. Testing at the protocol layer is the most cost-effective way to load test your APIs and static sites.

Best For
APIs, Simple Websites
Fuel Consumption
Loadster Fuel

Simulate traffic spikes and floods

for websites, web apps, and APIs

  • Load Testing for Websites

    Website Load Testing

    Record scripts with the free Loadster Recorder browser extension.

    Play them back with thousands of bots from 24 cloud regions across the globe.

  • Load Testing for Web Apps

    Web App Load Testing

    Loadster is a powerful way to test modern web applications.

    Automatically navigate complex authentication flows, execute client-side JavaScript, and implement your own control flow with code blocks.

  • Load Testing for APIs

    API Load Testing

    Load test any kind of HTTP API at the protocol layer -- including REST, GraphQL, JSON-RPC, & XML-RPC APIs.

    Import your scripts from Postman or OpenAPI/Swagger.

Accelerate your load testing

with a faster feedback loop

  • Step 1

    Rapidly create your test scripts

    Record load test scripts right in your browser, with the Loadster Recorder extension for Chrome or Firefox. Just step through your site like a real user would while Loadster records every step into a script. After recording, play your script back in real time, and edit it to perfection with Loadster's interactive script editor.

    It's simple to add custom validation and capture server responses to reuse later in the script. Not powerful enough for you? Try JavaScript Code Blocks for advanced control flow, looping, and conditionals.

  • Step 2

    Launch distributed cloud tests in seconds

    Configure your test scenario with groups of bots in regions of your choosing, running your scripts, ramping the load up and down, to simulate the geographically distributed traffic you see in the real world.

    Loadster's got what you need to run globally distributed cloud tests with minimal setup. No need to deploy your own instances to run test infrastructure! In about 90 seconds, Loadster can launch tens of thousands of bots across hundreds of cloud instances in regions of your choosing.

  • Step 3

    Analyze results with quick reporting

    While a load test runs, Loadster gives you realtime metrics on response times (average and percentile), network and transaction throughput, errors, and more.

    After it finishes, the same data is instantly available in a test report you can hold on to or share with your team.

    The metrics and report data inform you how your site handled the traffic, what kind of performance your real users can expect when the site's under a similar amount of load, and where the hot spots and bottlenecks might be.

Load testing for web apps

built to move fast

  • Speedy script recording

    Speedy script recording

    Record scripts right in your browser with the free Chrome or Firefox extension. Or add steps manually.

  • Browser based editing

    Browser based editing

    Add steps, edit them, and tweak your script to perfection. All in your web browser.

  • Rapid script feedback

    Rapid script feedback

    Play scripts from your web browser, and watch in real time as each step runs. Repeat as necessary!

  • Detailed diagnostics

    Detailed diagnostics

    After your script runs, view the full HTTP request and response from every step, both headers and body.

  • Fully managed cloud

    Fully managed cloud

    No need install any infrastructure! Loadster spins up fully managed cloud instances in about 90sec.

  • Live stream test results

    Live stream test results

    As a test runs, watch 10+ charts in real time. Monitor response times, throughput, errors, and more.

  • Automatic test reports

    Automatic test reports

    Loadster generates a full test report with charts and tables after every test. No more manual reporting!

  • Team collaboration

    Team collaboration

    Anyone on your team can create scripts, run tests, and share results. Make scalability a team effort!

Test from 24 global cloud regions

or your own self-hosted engines

Loadster can launch thousands of bots from your choice of cloud regions in 1-3 minutes. You can also self-host your engines to test privately hosted applications that aren't reachable from the cloud.

Loadster world coverage

Flexible pricing

to fit the way you test

  • Loadster Fuel

    Pay as you go, from $119 per 1000 bot hours

    Buy fuel and run load tests in any of 24 Loadster Cloud regions. No commitment. Simply purchase more fuel when you run out!

    View Loadster Fuel Pricing
  • Monthly Plans

    Run tests anytime, from $399 a month

    Run frequent tests at a predictable price. Load test anytime without burning fuel. The best option if you load test regularly!

    View Monthly Plan Pricing

Move fast
don’t crash

Ready to reduce the risk of site crashes?
Load testing gives you the confidence your site can handle it.

Start testing for free

The load testing tool of choice

for some pretty awesome people

  • Our customers at Nginx
  • Our customers at Wells Fargo
  • Our customers at Amazon
  • Our customer Queensland Government
  • Our customers at Accenture
  • Our customers at Yale University
  • Our customers at HBO
  • Our customers at Mint Mobile
  • Our customers at KPMG
  • Our customers at Perficient
  • Our customers at Dell
  • Our customers at Pearson