Kimi K2 ThinkingOpen Weight
Kimi K2 Thinking is an AI model released by Moonshot AI on Thursday, Nov 6 2025, 7 days after Kimi Linear. It is an open-weight model — the trained weights are available to download and run. It is a 1T parameter model with a 256k token context window. Benchmark results (shown below) cover SWE-Bench Verified.
Benchmarks
About Kimi K2 Thinking
Kimi K2 Thinking, released November 6, 2025, added a full reasoning mode to Moonshot's trillion-parameter K2 line and was billed for long-horizon agentic work: the model was trained to sustain hundreds of consecutive tool calls without human intervention, interleaving thinking with action across a 256K context window.
At release it posted the best agentic-search results of any open-weight model, including a leading score on Humanity's Last Exam with tools, and 71.3% on SWE-Bench Verified. Landing weeks before Claude Opus 4.5 and GPT-5.2, it made the strongest case yet that open weights could compete in the reasoning era. Kimi K2.5 followed in January 2026.
Kimi K2 Thinking — frequently asked questions
- When was Kimi K2 Thinking released?
- Kimi K2 Thinking was released by Moonshot AI on Thursday, Nov 6 2025.
- Who made Kimi K2 Thinking?
- Kimi K2 Thinking was built by Moonshot AI. Chinese AI company building the Kimi family of models. Founded in 2023, known for long-context and efficient MoE architectures.
- What benchmark scores did Kimi K2 Thinking get?
- Kimi K2 Thinking reports 1 tracked benchmark score — SWE-Bench Verified: 71.3%. Scores are the figures published at release by Moonshot AI.
- What is the context window of Kimi K2 Thinking?
- Kimi K2 Thinking has a context window of 256k. That is the maximum amount of input plus output the model can hold in a single request.
- How many parameters does Kimi K2 Thinking have?
- Kimi K2 Thinking is reported at 1T parameters.
- Is Kimi K2 Thinking open source?
- Partly. Kimi K2 Thinking is an open-weight model: the trained weights are free to download and run locally or on your own infrastructure, but the training data and code are not fully released and the license may restrict some commercial uses. It is not open source in the strict sense.
- What came before and after Kimi K2 Thinking?
- Moonshot AI's previous tracked release was Kimi Linear on Oct 30 2025, 7 days earlier. It was followed by Kimi K2.5 on Jan 27 2026.