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Kimi / MoE

Kimi-K3

A cluster model with a new attention design

Open-weight releaseSources checked 2026-09-13

K3 belongs on a shortlist for long-context coding and multimodal agents when a dedicated cluster is already a realistic option. The interesting change is the combination of Kimi Delta Attention, gated latent attention and Attention Residuals; scaling from K2’s 1T to 2.8T is only part of the story.

2,800Breported total parameters
104Bactive parameters per token
1,048,576configured token positions

Publisher-reported, rounded model count; not an exact tensor census. Multimodal components and packaging can change the artifact size.

Evaluate it for

Long repository tasks and multimodal agent evaluations on a high-memory cluster.

Choose another path when

A single workstation, a small H100 allocation, or a deployment that requires a mature generic attention backend.

Release context

Why this release matters

K2 used latent attention throughout. K3 combines a recurrent state with selective attention, changing how an engine manages cached prefixes and long requests. Its open release includes supporting kernels and communication work, so adopting the model also means adopting a newer runtime stack.

The July 16 announcement preceded the public weights by eleven days.

Release evidence · Announced 2026-07-16 · Weights 2026-07-27 · Follow the Kimi timeline →

Deployment starting points

Which hardware, how many, at what precision?

Start with an exact artifact and an engine that supports it. A configuration below is evidence of a documented path; its device count does not promise a particular throughput or concurrency.

Runtime recipe

8 × GB300 GPUs

GPUs within an NVLink system; this is not a count of whole racks.

Mixed MXFP4

vLLM K3 image

Minimum documented GB300 configuration. CUDA 13 image requires an r580+ driver; production concurrency may need more GPUs.

Checkpoint and source

moonshotai/Kimi-K3

Checked 2026-09-13. Read the documented setup →

Hardware specifications and interconnect →

1,560.86 GB of tensor data in the pinned index

This is the index’s reported tensor payload, in decimal GB. It excludes file headers and runtime memory. Mixed precision, conversion and host/device placement determine how much GPU memory the loaded model needs.

Inspect the exact index metadata →
Capacity screen: would the weights fit?

This estimates inference memory for a hypothetical uniform precision. It is useful for rejecting an allocation that is too small. It does not establish a working deployment or estimate training memory.

A uniform-precision GPU count would hide this model’s component layout. Publisher-reported, rounded model count; not an exact tensor census. Multimodal components and packaging can change the artifact size. Use the documented artifact and placement path above; no GPU count is inferred here.

Architecture in practice

What the serving engine has to do

Two kinds of layers retain two kinds of state.

A token enters a layerthe layer type selects its pathRecurrent layerupdate a compact stateAttention layerread retained token historyRecurrent statemaintained for this sequenceAttention cachelayout depends on the model

Hybrid attention does not mean zero request state.

A full-attention formula cannot describe every layer.

Schematic of a hybrid attention stack, not a literal layer ordering. Recurrent layers update a compact state; attention layers retain their own history. Both kinds of state matter for prefix reuse and concurrent requests.

Mechanism schematic based on the pinned model card and configuration. It explains a design principle; it is not a full implementation graph.

Inspect the full checkpoint specifications
Inspected fields for this exact revision. KV heads alone do not describe latent, hybrid or shared-cache layouts.
Exact checkpointmoonshotai/Kimi-K3
Text model typekimi_linear
Layers93
Hidden width7,168
Attention / KV heads96 / 96
Head dimensionNot verified
Routed / selected experts896 / Not verified
Configured positions1,048,576
Documented extensionNot recorded for this checkpoint
Inputs → outputtext, image, video → text
License metadatakimi-k3 · custom terms

Open weights do not imply unrestricted use. Read the applicable license terms linked from the pinned card.

A useful comparison

What else belongs on the shortlist?

K2.7-Code is the lower-storage Moonshot coding baseline; Qwen’s 2.4T checkpoint is a text-only cluster alternative.

12 Jun 2026

Kimi-K2.7-Code

A coding upgrade without a new size class

1,000B reported total · text + image + video

12 Aug 2026

Qwen3.8-2.4T-A95B

Large-scale text reasoning, with large-scale residency

2,400B reported total · text

These are editorial comparison candidates. We have not run a matched quality or serving benchmark, so this is not a ranking.

Prepare to explain it

The interview lesson

Explain why 104B active parameters can reduce token compute while 2.8T stored parameters still determine cluster residency. Then describe the recurrent-state and attention-cache split.

Attention layouts · Quantization · Courses and worked examples

For a deployment evaluation, record exact weights, precision, engine, device count, interconnect, prompt/output lengths and concurrency. Report task success, errors, TTFT, TPOT and useful throughput together.

Sources and citation

Our assessment is editorial judgment based on the linked architecture and deployment evidence. Model facts are publisher-reported or attributed to runtime maintainers; no independent GPU benchmark was run.

AI Infra Interviews, “Kimi-K3: release, architecture and deployment”, checked 2026-09-13. Preserve this date and the exact checkpoint when citing.

Model and research notes as JSON · Moonshot AI profile