Frequently Asked Questions


Loadster handles most cookies automatically, but sometimes you need to manually set a cookie yourself. An example of when this might be necessary is if you’re trying to piggyback on existing sessions without actually logging in. […]

How do I parse and validate a JSON response?

When you’re testing a JSON API, don’t just trust the HTTP 2xx responses to mean that everything’s working as expected. Add validation to look at the response bodies coming back and make sure they’re valid JSON and contain the right data. […]

How do I parse and validate an XML response?

When load testing XML web services (like SOAP, XML-RPC, and some RESTful services for example), it’s a good idea to parse the responses to make sure they are well-structured and contain the expected data. […]

How can I play a script that needs to reach a site on a private network?

If your site is on a private network that’s unreachable from the rest of the internet, you’ll need to self-host a Loadster Engine on your own network. […]

How can I ignore socket errors due to an untrusted TLS/SSL certificate?

Loadster normally refuses to talk to sites with untrusted or self-signed certificates, like a normal browser would. If it’s your own site and you want to trust it, you can override this behavior. […]

Load Testing

What’s the best way to calculate how many v-users I need for a load test?

Let’s say you know how much total traffic or transactions you need to simulate in a time period. How do you work backwards to estimate how many concurrent v-users it will take to get the job done? […]

More FAQs

We’ll be adding many more frequently asked questions here. If there’s something you would like to see, please email