Version: 3.7.x

What is JATOS

JATOS (Just Another Tool for Online Studies) helps you set up and run your online studies on your own server.

New: MindProbe, a free server for hosting online experiments. Powered by JATOS. Sponsored by the European Society for Cognitive Psychology (ESCoP) with Journal of Cognition as their official journal and OpenSesame.

Please complete our short survey on how (much) you use JATOS (ca. 3 min). It’s very important for us!

Run studies on your own server. This means that you keep complete control over who can access your result data and can comply with your ethics.
Studies run on mobile phones, tablets, desktops, and lab computers - any device with a browser.
Use tools like jsPsych, lab.js, OSWeb/OpenSesame, or PsyToolkit to prepare your study - or write all HTML / JavaScript / CSS yourself and have full control.
Run group studies where multiple workers interact with each other in real-time.
It’s GUI-based, so there's no need to use the terminal to talk to your server.
Recruit participants via MTurk, Prolific etc.
It's open-source and free to use.
Manage workers, to e.g. make sure that each participant does your study only once.
Export/Import studies to facilitate exchange with other researchers.
You can try out JATOS on cortex, our test server.

Watch an introduction video:

JATOS is free and open-source and released under the Apache 2 Licence. The source code is available on GitHub.

Over 100 studies have sucessfully collected data using JATOS already! Please cite us if you use JATOS for your research.