Open Variable Index

A searchable map of variables observed in the global corpus of scientific knowledge, powered by data from the System Public Graph

Explore variables

The Open Variable Index is designed for researchers choosing variables for their own studies or looking for studies related to their variable of interest, and is intended to enable the scientific field to formalize the variables that are used for experimentation and publication.

Variables indexed
5,647,297
Studies covered
844,435
Variables grounded
800,551
Latest release (10/16/26)
v1

How it works

Choose a variable for study

See what a variable is called, how others have measured it, and whether it has a persistent identifier

Find studies that measure it

See papers that measure the variable chosen, even as a co-variate or outside the field of focus

Download the whole index

No account is required to download or cite a release

What will you explore?

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