Pay as you go load testing

with Loadster Fuel

How much fuel

does it take to run a test?

Bot Type

Protocol Bots
Browser Bots

Test Size

10,000 Bots

Test size bar chart
Test size bar filling chart
Bar range



Duration bar chart
Duration bar filling chart
Bar range

1,000 Fuel Units


about Loadster Fuel

  • How much Loadster Fuel do I need?

    Fuel consumption depends on 3 factors: whether you're running Protocol Bots or Browser Bots, how many bots you're running, and the duration of the test. Try out the Fuel Estimator above to estimate how much fuel you'll need for each test, or start with your free starter fuel to get a feel and then work your way up to bigger and bigger tests.

  • What are Protocol Bots and Browser Bots?

    Protocol Bots are for running protocol scripts, which are a sequence of HTTP/HTTPS requests. They're best for low-level testing of APIs and simple websites. Browser Bots automate full-featured headless Chrome browsers. They're ideal for testing complex web applications, especially those with lots of client-side JavaScript or WebSockets. Browser Bots burn more fuel than Protocol Bots.

  • What is a "bot hour"?

    A bot is a virtual user (also known as a v-user), simulated by Loadster for the purpose of load testing your site. In a load test, bots play your scripts over and over. A unit of Loadster Fuel is enough to power one bot for one hour, so we call it a "bot hour". You can have fractional bot hours too: 1 bot for 15 minutes is 0.25 bot hours.

  • Do bot hours get rounded up?

    No! Unlike some other load testing platforms, Loadster does not round up the hours. We only deduct fuel for the exact amount of time your bots are allocated for a load test, down to the second. For example, a 6-minute test with Protocol Bots only uses 0.1 unit of fuel per bot.

  • Does Loadster Fuel ever expire?

    Loadster Fuel that you purchase pay-as-you-go never expires, and will remain in your account forever until you use it. In the past we've offered monthly fuel discount plans, and fuel you've accumulated from those plans may be lost if you cancel the plan, unlike pay-as-you-go fuel.

  • Can everyone on my team share the same Loadster Fuel?

    Sure. Invite your colleagues to your Loadster team from the dashboard. Whenever anyone on your team runs a load test, fuel will be deducted. Any user on your team can run tests, and any admin user on your team can top off the fuel.

  • Can Loadster Fuel be used for cloud testing?

    Absolutely. Loadster will automatically spin up engines in any of 24 cloud regions all over the world. When you're cloud testing, you don't have to install the engines yourself or launch any cloud instances — Loadster does it all automatically. All cloud fees are included in the price of the fuel.

  • Can Loadster Fuel be used for on-premises load testing?

    Yes it can. Just install a Loadster Engine in your own environment, and you can use your fuel to run load tests from self-hosted engines just like you can for cloud engines. Fuel consumption is no different whether you are running on-premises or in the cloud.

  • Why do Browser Bots use more fuel than Protocol Bots?

    Browser Bots automate a full Chrome browser, while Protocol Bots only require an HTTP client. The hosting costs are substantially higher for real browsers, and so is the level of sophistication required to automate all those browsers in parallel, so the fuel consumption of Browser Bots is higher.

  • Can I get a monthly plan instead of pay-as-you-go?

    Absolutely! We also offer Monthly Plans that let you run pretty much all the tests you need to, without burning any Loadster Fuel. If you have Loadster Fuel and a Monthly Plan, your tests will be run with the plan, and the fuel will remain unused.

Get 50 units of fuel
with your free account!

No credit card required.

Start load testing and get quick results, with the first 50 bot hours totally free.

Start testing for free

For more information please email

Loadtser dashboard