Kimi K2 (Sep 2025) | Epoch AI

ECI

N/A

Moonshot

Sep. 5, 2025

Open weights

Kimi K2 (Sep 2025) is an open-weights model from Moonshot, released September 5, 2025.

Kimi K2 (Sep 2025) vs select alternatives

Domain	Benchmark	Kimi K2 (Sep 2025) Moonshot Sep. 5, 2025 Open weights	GPT-5 OpenAI Aug. 7, 2025 Closed weights	Grok 4 xAI Jul. 9, 2025 Closed weights	Gemini 2.5 Pro (Jun 2025) Google DeepMind Jun. 5, 2025 Closed weights
Long context	ForecastBenchBest score 62.5	59.8	61.4	60.9	60.4
	Fiction.liveBenchBest score 97%	67%	97%	94%	92%
Software engineering	ALE-BenchBest score 2951	267	1162	—	786
	Aider PolyglotBest score 88%	59%	88%	80%	83%
	WeirdML (v2)Best score 94%	37%	61%	46%	54%

Model metadata

General
Organization	Moonshot
Release date	Sep. 5, 2025
Model accessibility	Open weights
Country	China
Knowledge cutoff	Unknown
Provider notes	Kimi K2: Open Agentic Intelligence

Pricing
Input price	—
Output price	—

Training
Parameters	1.0e12
Training compute	3.0e24 FLOP
Training hardware	NVIDIA H800 SXM5
Training time	Unknown
Training dataset size	1.6e13 datapoints