What is available now?
Source: Kimi K3 launch post and Kimi K3 API guide.
Kimi K3 at a glance
Moonshot has not yet published the technical report or exact checkpoint files. Treat any more precise parameter breakdown, storage size, runtime command, or performance claim as provisional until those artifacts arrive.
Can you run Kimi K3 locally?
No — not today. Kimi K3 is available now through Moonshot’s hosted API, but the downloadable weights have not shipped yet (promised by July 27, 2026). Even when the weights arrive, K3’s ~1.4 TB weight floor at 4-bit precision rules out every consumer and prosumer setup. Moonshot’s own recommendation is a supernode with 64 or more accelerators. Eight DGX Sparks pool 1 TB of unified memory and still fall 376 GB short. See the DGX Spark memory math for the full calculation.Kimi K3 hardware requirements
No consumer or prosumer setup holds K3. At exactly 4 bits per parameter, 2.8T parameters need about 1.4 TB for the weights alone — before microscaling metadata, runtime buffers, activations, and context state. For scale: eight DGX Sparks pool 1 TB of unified memory and are still at least 376 GB short of the raw weight floor, NVIDIA currently documents Spark clusters only to four nodes, and Moonshot recommends serving K3 on a supernode with 64 or more accelerators. See the DGX Spark memory math for the full calculation, cluster table, and network constraints.Need something you can download today? Compare all current Kimi models — Kimi K2.6 and K2.7-Code are open-weight now and run on server-class hardware.
Why the architecture matters for self-hosting
K3 is not simply a larger K2 checkpoint. Four changes matter to anyone planning to serve it:- Kimi Delta Attention (KDA) — a hybrid linear-attention design that makes million-token prompts cheaper to prefill. It needs matching kernels and cache semantics: Moonshot says conventional prefix caching does not map cleanly to KDA and that its vLLM prefill-cache contribution ships with the weights. A runtime that merely loads the weights is not automatically K3-compatible.
- Attention Residuals (AttnRes) — layers selectively retrieve useful representations from earlier depth instead of adding every layer’s output with fixed weight. Moonshot’s AttnRes paper reports more stable information flow in deeper models.
- Stable LatentMoE — 16 of 896 experts route per token. Sparse activation cuts per-token compute, but it does not shrink the stored checkpoint: every expert must stay resident across the serving cluster, which makes fast interconnects a first-order requirement.
- Native MXFP4 — quantization-aware training ran from the supervised fine-tuning stage onward, targeting MXFP4 weights and MXFP8 activations. This is the intended serving format, not a community quant — so the 4-bit figure above is a floor, not a compromise.
K3 API behavior to preserve
If you test K3 through Moonshot’s API now, or validate a self-hosted runtime later, these protocol details matter:- K3 always reasons. Use the top-level
reasoning_effort: "max"; do not send K2.x’sthinkingparameter. - Streaming responses separate reasoning into
reasoning_contentand the final answer intocontent. - For multi-turn conversations and tool loops, replay the complete assistant message, including preserved reasoning and tool-call fields. Returning only
contentcan destabilize later turns. max_completion_tokensdefaults to 131,072 and can be set as high as 1,048,576.- The launch API fixes sampling values. Moonshot recommends that you omit
temperature,top_p,n, and penalty parameters rather than override them. - Public image URLs are not accepted. Send base64 data or an
ms://<file-id>reference.
Connect K3 with Tokios after the weights arrive
Tokios belongs after a local runtime. It doesn’t download the model or replace vLLM. When Moonshot and the runtime maintainers publish a supported K3 serving path:1
Verify the official artifacts
Confirm the repository is linked by Moonshot. Read the model card, license, checkpoint manifest, supported accelerator list, and recommended parallelism settings. Do not infer them from K2.
2
Serve K3 on the supported cluster
Follow the published vLLM or other runtime instructions. Confirm the local server can complete a streaming request, preserve
reasoning_content, and execute a multi-turn tool loop on its own /v1 API.3
Pair the Tokios connector
Install the connector on a node that can reach the serving endpoint. In the dashboard, open Setup, select Start pairing, and use the one-time
TKS-XXXX-XXXX claim code.4
Register a deployment
Point the connector at the cluster’s OpenAI-compatible
/v1 base URL. Register the upstream model id under a public deployment name such as kimi-k3-tunnel.5
Create an API key
In the Keys tab, click Create key. Copy the
sk-tok-… key now — it’s shown only once.6
Test before sharing the endpoint
Test streaming, long turns, vision, structured output, and tool calls through
https://api.tokios.com. Use a dedicated sk-tok-… API key and keep the initial context short while you validate memory use.Call it from anywhere
Once that path is verified, clients call your deployment name rather than the upstream model id:Launch caveats
- The weights, model card, license, technical report, checksum manifest, and self-hosting commands are still pending.
- K3 benchmark results are Moonshot-reported. Independent reproduction must wait for the weights and evaluation setup.
- Moonshot warns that losing preserved reasoning history, or switching another model’s existing session to K3, can make output unstable.
- K3 is trained for long, difficult tasks and can act too proactively when instructions are ambiguous. Put explicit boundaries in your system prompt or
AGENTS.md. - A 1M-token limit is a maximum, not a target. Long contexts increase prefill time, cache storage, and inference cost.
FAQ
How much VRAM does Kimi K3 need?
How much VRAM does Kimi K3 need?
At its native MXFP4 precision (4 bits per parameter), K3’s 2.8T parameters need about 1.4 TB for weights alone — before block scales, runtime buffers, activations, and KV cache. That is roughly 11 DGX Sparks at their 128 GB each, just for the raw weight floor. In practice you need 14-16 Sparks minimum for a hypothetical distributed serving stack, and NVIDIA only documents Spark clusters up to 4 nodes.
Can Kimi K3 run on a DGX Spark cluster?
Can Kimi K3 run on a DGX Spark cluster?
Not practically. Eight DGX Sparks give you 1 TB of unified memory — 376 GB short of the weight floor. NVIDIA’s documented Spark topology tops out at 4 nodes (512 GB), and Moonshot targets K3 at supernodes with 64 or more accelerators. For Spark-scale models today, see DGX Spark model compatibility.
Is Kimi K3 open source?
Is Kimi K3 open source?
Moonshot says K3 will ship with downloadable weights by July 27, 2026, but the license, model card, and checkpoint files are not published yet. Calling it “open” is accurate only after the weights and license land. Kimi K2.6 and K2.7-Code are open-weight today — see the Kimi model family.
How do I run Kimi K3?
How do I run Kimi K3?
Today, through Moonshot’s hosted API using the model id
kimi-k3. After the weights ship, you serve the checkpoint on a supported cluster (vLLM with KDA cache support is expected) and call its OpenAI-compatible /v1 endpoint. Tokios can front that local endpoint with scoped API keys — see Connect K3 with Tokios above.What is Kimi K3's context length?
What is Kimi K3's context length?
1,048,576 tokens (1M). The
max_completion_tokens parameter defaults to 131,072 and can be set as high as the full context window. Long contexts increase prefill time, cache storage, and inference cost — 1M is a maximum, not a target.What architecture does Kimi K3 use?
What architecture does Kimi K3 use?
K3 is a Mixture-of-Experts model with 4 key innovations: Stable LatentMoE (16 of 896 experts activate per token, ~50B active), Kimi Delta Attention (hybrid linear attention for efficient million-token prefill), Attention Residuals (depth-wise information routing), and native MXFP4 (quantization-aware training from SFT onward). These are not drop-in compatible with standard transformer serving — KDA in particular needs matching kernels and cache semantics.
Kimi K3 on DGX Spark
The full memory math, cluster constraints, and launch-evidence table.
Kimi models
Compare K3 with the downloadable K2.6 and K2.7-Code, and self-host Kimi today.
Model serving and scaling
Understand tensor, pipeline, and expert parallelism before you plan a frontier-scale cluster.
Quickstart
Pair a connector and register a local model that is available today.