lab.js is a tool for constructing browser-based studies built for (but not limited to) the social and cognitive sciences. Studies can be assembled using a graphical builder, or through code. In either case, lab.js takes care of study presentation, response collection and data storage, while providing the greatest possible flexibility with regard to study design.


Assemble studies with ease using a graphical interface.

Using the builder tool, studies can be constructed with a basic knowledge of HTML alone. The interface is designed to make users of native experimental software feel at home immediately.

Even though the interface simplifies many aspects of study design, full access to the underlying code is always possible, so that experiments can be adapted to even complex requirements.

Studies are assembled
from individual components ...
... for example loops,
which repeat parts of a study ...
... an online preview
shows changes immediately.

JavaScript library

Studies can be programmed from scratch for maximum customizability and control.