Video tutorials
Narrated walkthroughs of Open Lab and of building tasks in the lab.js builder. Each has subtitles in 12 languages, chapters and a transcript, the files to follow along directly under the player, and a link to its docs page.
Files for this video
- ↓ two-choice-reaction-task-v2.jsonThe task's new file from this video: each circle stays on screen for 1.5 s instead of 1 s. Nothing else differs.
Open Lab: from a first study to data
Add your own lab.js task
2:26 · narrated, with subtitles in 12 languages · recorded in November 2026
The three tabs of a task step, the My tasks page and a task's own page with its file history. A new file becomes revision 2, the study runs it from the next participant on, and values the study set itself stay as they were.
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