Kimi releases K3.1 Pro, a 1M-token open-weight model

Kimi, a Chinese AI research lab, has announced K3.1 Pro, an open-weight language model in the 3-trillion-parameter class with a 1-million-token context window. The company also released K3.1 Pro Highspeed, a faster variant. Full model weights are scheduled to become available by November 4.

The models were benchmarked on multiple evaluation suites including Terminal-Bench 4.0, Terminal-Bench Science, DeepSWE, SWE-Marathon, and PostTrainBench, suggesting competitive performance on reasoning and coding tasks.