AI Models · Open-Source vs Paid

Kimi K3 Open vs GPT-4.1 Paid

Kimi K3 vs GPT-4.1 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 GPT-4.1 if you want frontier capability through a managed API with zero infrastructure to run.

Kimi K3 vs GPT-4.1 specs

SpecKimi K3GPT-4.1
MakerMoonshot AIOpenAI
TypeOpen-weightProprietary
Context window1M tokens1M tokens
Input price$3/M · free self-host$2/M
Output price$15/M · free self-host$8/M
Vision / multimodalYesYes
Tool / function callingYesYes
Self-hostableYesNo (API only)
LicenseModified MITProprietary

Feature comparison

CapabilityKimi K3GPT-4.1
Open weights (downloadable)
Self-hostable
Runs fully offline
Vision / multimodal
Tool / function calling
1M+ context window

Benchmarks: Kimi K3 vs GPT-4.1

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

Kimi K3
GPT-4.1
Intelligence index
57.1
19.4
Coding index
76.2
GPQA
93.5%
66.6%
Humanity's Last Exam
44.3%
4.6%
Long Context Reasoning
74.7%
61%
SciCode
58.7%
38.1%
τ-Bench Banking
33.4%
Terminal-Bench
85%
Math index
34.7
MMLU-Pro
80.6%
LiveCodeBench
45.7%
MATH-500
91.3%
AIME
43.7%
AIME 2025
34.7%
IFBench
43%
τ²-Bench
47.1%
Terminal-Bench Hard
13.6%
Speed
39.4 tok/s
150.8 tok/s
Latency
2.62s
0.56s
Intelligence per $
9.5
5.5

Benchmark data by Artificial Analysis.

How Kimi K3 and GPT-4.1 score

🏆 Best value & openness: Kimi K3 (4.6 vs 3.2 / 5)
CriterionKimi K3GPT-4.1
Cost-efficiency3.03.5
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...

GPT-4.1 Paid

OpenAI · Proprietary

GPT-4.1 is a flagship large language model optimized for advanced instruction following, real-world software engineering, and long-context reasoning. It supports a 1 million token context window and outperforms GPT-4o and...

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
GPT-4.1 Mini

Frequently asked questions

Is Kimi K3 as good as GPT-4.1?

Kimi K3 is open-weight and competitive on many tasks, but GPT-4.1 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. GPT-4.1 is API-only and cannot be self-hosted.

Kimi K3 vs GPT-4.1 — 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 GPT-4.1 if you want frontier capability through a managed API with zero infrastructure to run.

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