AI Models · Open-Source vs Paid

Kimi K3 Open vs o3 Paid

Kimi K3 vs o3 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 · olud.ai

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

Kimi K3OpenMoonshot AI
$0.8 /M input
$13.5 /M outputNo per-token fees if you self-host
TypeOpen-weight
Context window1M tokens
MultimodalYes
Self-hostYes
o3PaidOpenAI
$2 /M input
$8 /M outputManaged API (no infra to run)
TypeProprietary
Context window200K tokens
MultimodalYes
Self-hostNo
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 o3 if you want frontier capability through a managed API with zero infrastructure to run.

Kimi K3 vs o3 specs

SpecKimi K3o3Winner
MakerMoonshot AIOpenAI–
TypeOpen-weightProprietaryKimi K3
Context window1M tokens200K tokensKimi K3
Input price$0.8/M · free self-host$2/MKimi K3
Output price$13.5/M · free self-host$8/Mo3
Vision / multimodalYesYes= Tie
Tool / function callingYesYes= Tie
Self-hostableYesNo (API only)Kimi K3
LicenseModified MITProprietaryKimi K3

Price gap & when to choose each

1.7×cheaper per output token

o3 is ~1.7× cheaper than Kimi K3 on output tokens ($8 vs $13.5 per M tokens).

Choose Kimi K3 if…
  • You want to self-host or run on your cloud
  • You need the longer 1M context window
  • You prioritize data privacy & control
  • You are building open or reproducible AI
Choose o3 if…
  • You want frontier performance through a managed API
  • You want the lower output price
  • You value reliability & ecosystem
  • You don't want to manage infrastructure

Feature comparison

CapabilityKimi K3o3
Open weights (downloadable)✓✗
Self-hostable✓✗
Runs fully offline✓✗
Vision / multimodal✓✓
Tool / function calling✓✓
1M+ context window✓✗

Benchmarks: Kimi K3 vs o3

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

Kimi K3
o3
Intelligence index
43.6
20.2
Coding index
76.2
–
GPQA
93.5%
82.7%
Humanity's Last Exam
46.9%
20.1%
Long Context Reasoning
88.7%
74.7%
SciCode
59.5%
–
τ-Bench Banking
46%
–
Terminal-Bench
85%
–
Math index
–
88.3
MMLU-Pro
–
85.3%
LiveCodeBench
–
80.8%
MATH-500
–
99.2%
AIME
–
90.3%
AIME 2025
–
88.3%
IFBench
–
71.4%
τ²-Bench
–
80.7%
Terminal-Bench Hard
–
37.1%
Speed
38.9 tok/s
111.4 tok/s
Latency
2.88s
5.59s
Intelligence per $
7.3
5.8

Benchmark data by Artificial Analysis.

How Kimi K3 and o3 score

🏆 Best value & openness: Kimi K3 (4.7 vs 3.0 / 5)
CriterionKimi K3o3
Cost-efficiency3.53.5
Context window5.04.0
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...

o3 Paid

OpenAI · Proprietary

o3 is a well-rounded and powerful model across domains. It sets a new standard for math, science, coding, and visual reasoning tasks. It also excels at technical writing and instruction-following....

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 K3 (batch)Kimi K2.6Kimi K2.7 CodeKimi K2.5Kimi K2 ThinkingKimi K2 0905Kimi K2 0711
Other variants tracked
o3 Proo3 (batch)o3 Minio3 Mini (batch)o3 Mini High

Frequently asked questions

Is Kimi K3 as good as o3?

Kimi K3 is open-weight and competitive on many tasks, but o3 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. o3 is API-only and cannot be self-hosted.

Kimi K3 vs o3 — 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 o3 if you want frontier capability through a managed API with zero infrastructure to run.

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