Kimi K2-Thinking-0905

Kimi K2 Thinking is the latest, most capable version of open-source thinking model. Starting with Kimi K2, it is built as a thinking agent that reasons step-by-step while dynamically invoking tools. It sets a new state-of-the-art on Humanity's Last Exam (HLE), BrowseComp, and other benchmarks by dramatically scaling multi-step reasoning depth and maintaining stable tool-use across 200–300 sequential calls. At the same time, K2 Thinking is a native INT4 quantization model with 256k context window, achieving lossless reductions in inference latency and GPU memory usage. Key features include deep thinking & tool orchestration with end-to-end training to interleave chain-of-thought reasoning with function calls, native INT4 quantization via Quantization-Aware Training (QAT) achieving lossless 2x speed-up, and stable long-horizon agency maintaining coherent goal-directed behavior across up to 200–300 consecutive tool invocations.

Benchmark results

Benchmark Score Tags Source
AIME 2025 100.0% self-reported llm-stats link →
BrowseComp 60.2% self-reported llm-stats link →
BrowseComp-zh 62.3% self-reported llm-stats link →
FinSearchComp-T3 47.4% self-reported llm-stats link →
FRAMES 87.0% self-reported llm-stats link →
GPQA 84.5% self-reported llm-stats link →
HealthBench 58.0% self-reported llm-stats link →
HMMT 2025 97.5% self-reported llm-stats link →
Humanity's Last Exam 51.0% self-reported llm-stats link →
IMO-AnswerBench 78.6% self-reported llm-stats link →
LiveCodeBench v6 83.1% self-reported llm-stats link →
MMLU-Pro 84.6% self-reported llm-stats link →
MMLU-Redux 94.4% self-reported llm-stats link →
Multi-SWE-Bench 41.9% self-reported llm-stats link →
OJBench 48.7% self-reported llm-stats link →
SciCode 44.8% self-reported llm-stats link →
Seal-0 56.3% self-reported llm-stats link →
SWE-bench Multilingual 61.1% self-reported llm-stats link →
SWE-Bench Verified 71.3% self-reported llm-stats link →
Terminal-Bench 47.1% self-reported llm-stats link →
WritingBench 73.8% self-reported llm-stats link →