From the source
Moonshot AI introduced Kimi K3.1 Pro, a 3T-class open-weight model with a 1-million-token context window, and a faster Highspeed variant, both available today on Kimi's apps and API.
- K3.1 Pro is a post-trained version of Kimi K3 with substantially larger post-training compute, which Moonshot says brings consistent gains across every domain.
- The company says the model matches or approaches the strongest proprietary models on coding, agentic and knowledge benchmarks.
- On Terminal-Bench 4.0 it scores 65.7%, ahead of GPT-6 Astra (58.2%) and narrowly behind Claude Opus 5.5 (66.4%), and on Kimi Code Bench 3.0 Long-horizon it scores 61.2%, above K3's 55.95%.
