Moonshot releases Kimi K3.1 Pro with a 1M-token window and says weights follow by 4 November

Moonshot says K3.1 Pro scores 65.7% on Terminal-Bench 4.0 against 66.4% for Claude Opus 5.5, by its own figures; the rivals' scores come from their own blog posts or the official leaderboard.

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Check our sources · 7 facts from 1 source

Moonshot AI released Kimi K3.1 Pro, the first model in its K3.1 series, with a 1-million-token context window. It also released Kimi K3.1 Pro Highspeed, which Moonshot says is two to three times faster. Both are available on Kimi.com, Kimi Work, Kimi Code and the Kimi API. Moonshot says the full model weights will be released by 4 November.

Moonshot describes K3.1 Pro as a post-trained version of Kimi K3 with substantially larger post-training compute. On Terminal-Bench 4.0, Moonshot says K3.1 Pro scores 65.7%, ahead of GPT-6 Astra at 58.2% and narrowly behind Claude Opus 5.5 at 66.4%.

On its own Kimi Code Bench 3.0 Long-horizon benchmark it scores 61.2%, against 55.95% for K3. The scores for GPT-6 Astra and Claude Opus 5.5 are the highest values those companies reported in their own blog posts or on the official leaderboard; Moonshot did not run them. Moonshot's figures for K3.1 Pro and K3 are its own.

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1 Introducing Kimi K3.1 ProMoonshot AI (Kimi) · 23 Oct 2026 · 7 facts

Open the source archived copy

Moonshot says Kimi K3.1 Pro is the first model in its K3.1 series, with a 1M-token (1-million-token) context window.
Toned down to what the source says
the first model in our new K3.1 series
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Moonshot says Kimi K3.1 Pro Highspeed delivers 2-3x the speed of K3.1 Pro.

which delivers 2-3× the speed of K3.1 Pro for more responsive interactions.
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Moonshot says K3.1 Pro and K3.1 Pro Highspeed are available today on Kimi.com, Kimi Work, Kimi Code, and the Kimi API.

Kimi K3.1 Pro and Kimi K3.1 Pro Highspeed are available today on Kimi.com, Kimi Work, Kimi Code, and the Kimi API.
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Moonshot says the full model weights will be released by Nov 4.

The full model weights will be released by Nov 4.
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Moonshot describes K3.1 Pro as a post-trained version of Kimi K3 with substantially larger post-training compute.

Kimi K3.1 Pro is a post-trained version of Kimi K3, with substantially larger post-training compute.
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Moonshot says that on Terminal-Bench 4.0, its own benchmark run with the Claude-Code harness, Kimi K3.1 Pro scores 65.7%, ahead of GPT-6 Astra (58.2%) and narrowly behind Claude Opus 5.5 (66.4%); the other models scores are the maximum values reported in their own blog posts or on the official leaderboard.
Toned down to what the source says
K3.1 Pro scores 65.7%, ahead of GPT-6 Astra (58.2%) and narrowly behind Claude Opus 5.5 (66.4%).
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Moonshot says K3.1 Pro scores 61.2% on Kimi Code Bench 3.0 Long-horizon, its internal benchmark, above K3's 55.95%.

K3.1 Pro scores 61.2%, above K3's 55.95%.
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