When was Kimi K2 (0905) released?

Kimi K2 (0905) was released by Moonshot AI on Friday, Sep 5 2025.

Who made Kimi K2 (0905)?

Kimi K2 (0905) 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 (0905) get?

Kimi K2 (0905) reports 2 tracked benchmark scores — SWE-Bench Verified: 65.8%; GPQA Diamond: 75.1%. Scores are the figures published at release by Moonshot AI.

What is the context window of Kimi K2 (0905)?

Kimi K2 (0905) 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 (0905) have?

Kimi K2 (0905) is reported at 1T parameters.

Is Kimi K2 (0905) open source?

Partly. Kimi K2 (0905) 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 (0905)?

Moonshot AI's previous tracked release was Kimi K2 on Jul 11 2025, 56 days earlier. It was followed by Kimi Linear on Oct 30 2025.

Kimi K2 (0905)Open Weight

Released Sep 5 2025

Kimi K2 (0905) is an AI model released by Moonshot AI on Friday, Sep 5 2025, 56 days after Kimi K2. 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, and GPQA Diamond.

Available from


Novita	$0.60	$2.50	256K	fp8

USD per 1M tokens

Benchmarks

Coding

SWE-Bench Verified

65.8%

#41 of 57

Reasoning & science

GPQA Diamond

75.1%

#43 of 59

Compare Kimi K2 (0905) with

Kimi K2 (0905)

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Frequently asked questions

: Kimi K2 (0905) was released by Moonshot AI on Friday, Sep 5 2025.
: Kimi K2 (0905) 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.
: Kimi K2 (0905) reports 2 tracked benchmark scores — SWE-Bench Verified: 65.8%; GPQA Diamond: 75.1%. Scores are the figures published at release by Moonshot AI.
: Kimi K2 (0905) has a context window of 256k. That is the maximum amount of input plus output the model can hold in a single request.
: Kimi K2 (0905) is reported at 1T parameters.
: Partly. Kimi K2 (0905) 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.
: Moonshot AI's previous tracked release was Kimi K2 on Jul 11 2025, 56 days earlier. It was followed by Kimi Linear on Oct 30 2025.