Brainback
journalproduct

Brain score 2.0

A refined formula, and a new share card.

product
Mar 5, 20265 minProduct team

The Brain score has been in the product since day one. Today it gets its first meaningful update.

The weights are the same: 40% recall, 30% calibration, 30% explain-back. What's changed is the calibration component. We now use a proper Brier-style calculation that accounts for the full distribution of confidence-outcome pairs, rather than the simpler binary comparison we shipped v1 with.

For most users the score won't move noticeably. For users with systematic over- or under-confidence, the new calibration score reflects the pattern more honestly. That is what it is supposed to do.

The share card has also been redesigned. Bigger number. Better typography. A weekly delta that reads at a glance. Share it, or just save it for yourself.


Filed by Product team on Mar 5, 2026. Under Product.

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