Definition
Testing data
Testing data is data used for an independent evaluation of an AI system before launch or after major change. It should represent real conditions without being used to train or tune the model, otherwise the evaluation becomes inflated.
Last updated: 25 June 2026
Why it matters
It gives leaders a more honest view of expected performance before a workflow depends on the system.
Signals to watch
- The data is held out
- Performance is measured independently
- Results inform launch or stop decisions