jsPsych is a JavaScript library for running behavioral experiments in a web browser. The library provides a flexible framework for building a wide range of laboratory-like experiments that can be run online. -jsPsych website

jsPsych free open source library written in JavaScript. It does not feature a graphical experiment builder interface like OpenSesame or Gorilla, and may therefore be more difficult to use for people with no programming experience. Nevertheless, it is a very powerful and flexible tool for coding online experiments, and includes a sizable collections of useful plug-ins.

Support and Advice

SOLO currently only provides very limited basic support for jsPsych, but recommends using it (together with Pavlovia or JATOS) for researchers with JavaScript experience. Given adequate programming prowess, jsPsych provides for a much cleaner and extensible environment than both OpenSesame/OSWeb and Gorilla.


jsPsych experiments can be hosted on Pavlovia, JATOS and Gorilla, all of which are free to use for FSW researchers. SOLO strongly recommends using one of these platforms and discourages researchers from hosting their experiments elsewhere.