AI Models · Open-Source vs Paid

Kimi K3 Open vs Claude Opus 4.8 Paid

Kimi K3 vs Claude Opus 4.8 compared — price per token, context window, multimodality, openness and which to choose. Can the open-source model replace the paid one? Full 2026 breakdown.

Prices & specs refreshed from live data · OpenSourceAI.tech

Open-model prices = cheapest provider via OpenRouter; official maker rates may be higher.

Choose Kimi K3 if you want to self-host, keep your data private and skip per-token fees — it's open-weight and runs on your own hardware. Choose Claude Opus 4.8 if you want frontier capability through a managed API with zero infrastructure to run.

Kimi K3 vs Claude Opus 4.8 specs

SpecKimi K3Claude Opus 4.8
MakerMoonshot AIAnthropic
TypeOpen-weightProprietary
Context window1M tokens1M tokens
Input price$3/M · free self-host$5/M
Output price$15/M · free self-host$25/M
Vision / multimodalYesYes
Tool / function callingYesYes
Self-hostableYesNo (API only)
LicenseModified MITProprietary

Feature comparison

CapabilityKimi K3Claude Opus 4.8
Open weights (downloadable)
Self-hostable
Runs fully offline
Vision / multimodal
Tool / function calling
1M+ context window

Benchmarks: Kimi K3 vs Claude Opus 4.8

Independent benchmark scores measured by Artificial Analysis. Higher is better (except latency).

Kimi K3
Claude Opus 4.8
Intelligence index
57.1
55.7
Coding index
76.2
74.3
GPQA
93.5%
92%
Humanity's Last Exam
44.3%
45.7%
Long Context Reasoning
74.7%
67.7%
SciCode
58.7%
53.5%
τ-Bench Banking
33.4%
27.6%
Terminal-Bench
85%
84.6%
IFBench
62.2%
τ²-Bench
94.4%
Terminal-Bench Hard
58.3%
Speed
39.4 tok/s
62.5 tok/s
Latency
2.62s
28.57s
Intelligence per $
9.5
5.6

Benchmark data by Artificial Analysis.

How Kimi K3 and Claude Opus 4.8 score

🏆 Best value & openness: Kimi K3 (4.6 vs 3.1 / 5)
CriterionKimi K3Claude Opus 4.8
Cost-efficiency3.03.0
Context window5.05.0
Openness5.01.5
Self-hosting5.01.0
Multimodality5.05.0

Scores come from live data — output price (cost), context length, open vs closed weights (openness & self-hosting) and vision/tool support (multimodality). Raw task quality isn't scored here; it depends on your benchmark — see the verdict.

What each model is

Kimi K3 Open

Moonshot AI · Open-weight

Kimi K3 is a 2.8T parameter open-weight multimodal reasoning model from Moonshot AI. It is suited for complex coding, knowledge work, and long-horizon agentic workflows, and is particularly strong at...

Claude Opus 4.8 Paid

Anthropic · Proprietary

Claude Opus 4.8 is Anthropic's most capable generally available model in the Opus family. It supports text, image, and file inputs with text output, with reasoning support and a 1M-token...

Other models in these families

These variants are tracked but not compared here — one page per family keeps the comparison readable.

Other variants tracked
Kimi K2.6Kimi K2.5Kimi K2.7 CodeKimi K2 0905Kimi K2 0711Kimi K2 ThinkingMoonshotAI Kimi Latest
Other variants tracked
Claude Opus 4.7Claude Opus 4.6

Frequently asked questions

Is Kimi K3 as good as Claude Opus 4.8?

Kimi K3 is open-weight and competitive on many tasks, but Claude Opus 4.8 may still lead on the hardest reasoning and agentic work. The gap keeps narrowing — benchmark both on your actual use case before deciding.

Can I run Kimi K3 locally?

Yes. Kimi K3 has open weights, so you can self-host it on your own GPUs or run it via a low-cost API. Claude Opus 4.8 is API-only and cannot be self-hosted.

How much cheaper is Kimi K3?

Kimi K3 costs $15/M output vs $25/M for Claude Opus 4.8 — roughly 2x cheaper via API, and free if you self-host.

Kimi K3 vs Claude Opus 4.8 — which should I pick in 2026?

Choose Kimi K3 if you want to self-host, keep your data private and skip per-token fees — it's open-weight and runs on your own hardware. Choose Claude Opus 4.8 if you want frontier capability through a managed API with zero infrastructure to run.

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