Leanstral 1.5 - Mistral AI

1 min read Original article ↗

Cat

June 30, 2026Blog

Public Previewv1.5

An updated Lean 4 formal proof engineering model optimised for automated theorem proving and autoformalization. 119B total parameters, 6.5B active.

Speed

Performance

Modalities

Context

256k

Max output

128k

Price

Free

Speed

Performance

Modalities

Context

256k

Max output

128k

Price

Free