LLMBenchmark.ai

Enter opens the highlighted result. Esc closes.

GPT-6 Luna vs Kimi K3

Updated October 21, 2026. 90 benchmarks have a result for both. Coding is ranked on the Vibe Coding Index; every other board is shown as published.

Replace GPT-6 Luna Replace Kimi K3
GPT-6 LunaOpenAI
Coding
71.4
Overall
38.1
Output $/M
$0.50
14
Kimi K3Moonshot AI
Coding
61.8
Overall
43.6
Output $/M
$11.936
76
vs boards won of 90 shared

Decision reading

Pick GPT-6 Luna for coding: it scores 71.4 on the Vibe Coding Index against 61.8 for Kimi K3.

Pick Kimi K3 when what matters is LMArena WebDev or Terminal-Bench 4 (Vals AI), where it leads.

Model AGPT-6 LunaOpenAI71.4/1002 independent benchmarksNo cost per solved taskModel BKimi K3Moonshot AI61.8/1002 independent benchmarks$0.81 per solved task
Shared results
90
GPT-6 Luna only
12
Kimi K3 only
27
Like-for-like categories
8 of 9

Shared results can support a head-to-head reading. Results only one model has describe coverage, not superiority.

Which one for your work

Each card is decided by one number both models carry. Where only one has it, the card says so and makes no call.

At a glance

Coding index
GPT-6 Luna 71.4 from 2 benchmarks, Kimi K3 61.8 from 2 benchmarks.
Widest category
Agentic work, 14.8 points apart on average over 14 shared benchmarks.
Widest single gap
LiveBench browser: GPT-6 Luna 72.0% against Kimi K3 16.0%, 56.0 points apart on a 0 to 100 scale.
Output price
GPT-6 Luna $0.50 against Kimi K3 $11.936 per million output tokens, 23.9x apart.
Context window
GPT-6 Luna takes 1.05M tokens, Kimi K3 1.05M.

Benchmark by benchmark

First the score: boards each model leads, per category, where both have a result. Then every board, a category to a fold; bars are each result on a 0 to 100 scale, so compare the two in a row, not one row with another.

Boards won, where both have a result
CategoryGPT-6 LunaBarsKimi K3Ties
Coding513
Intelligence02
Agentic work410
Reasoning010
Math33
Knowledge06
Web design17
General125
All shared boards1476
CodingLike-for-likeFour of these boards feed the Vibe Coding Index513
Coding benchmarks for GPT-6 Luna and Kimi K3
BenchmarkGPT-6 LunaKimi K3Leader
LiveBench coding84.5%59.3%GPT-6 Luna
LMArena WebDev15781655Kimi K3
AA Coding IndexNot measured76.2Only Kimi K3 measured
LiveCodeBench (Vals AI)Not measured87.2%Only Kimi K3 measured
SWE-bench Verified (Vals AI)Not measured93.4%Only Kimi K3 measured
Terminal-Bench 4 (Vals AI)13.6%17.2%Kimi K3
Vibe Code Bench (Vals AI)81.7%85.0%Kimi K3
Code migration (Vals AI)42.5%16.1%GPT-6 Luna
ProgramBench (Vals AI)0.5%2.0%Kimi K3
IOI (Vals AI)55.6%48.9%GPT-6 Luna
Terminal-Bench 2.1 (Vals AI)73.0%80.9%Kimi K3
SWE-bench Multimodal (Vals AI)37.5%44.2%Kimi K3
Vibe Code Bench 1-100 (Vals AI)Not measured18.2%Only Kimi K3 measured
CyberBench (Vals AI)76.3%75.2%GPT-6 Luna
SciCode54.6%59.5%Kimi K3
FrontierCode42.4%44.2%Kimi K3
FrontierSWENot measured25.9%Only Kimi K3 measured
WeirdMLNot measured82.6%Only Kimi K3 measured
ALE-Bench1576.91524.5GPT-6 Luna
LMArena Text: coding14371508Kimi K3
LMArena Text: software and IT14231499Kimi K3
LMArena WebDev: React15731670Kimi K3
LMArena WebDev: HTML15951644Kimi K3
LMArena WebDev: from an image15711579Kimi K3
Neither model has a result on the other 14 boards here
IntelligenceLike-for-likePublic boards, shown as published, kept out of the index02
Intelligence benchmarks for GPT-6 Luna and Kimi K3
BenchmarkGPT-6 LunaKimi K3Leader
AA Intelligence Index38.143.6Kimi K3
Epoch Capabilities Index156.8157.9Kimi K3
Agentic workLike-for-likePublic boards, shown as published, kept out of the index410
Agentic work benchmarks for GPT-6 Luna and Kimi K3
BenchmarkGPT-6 LunaKimi K3Leader
AA Agentic IndexNot measured50.0Only Kimi K3 measured
Design Arena: agents building web apps11891296Kimi K3
Design Arena: agents building full-stack apps11581315Kimi K3
Design Arena: agents building mobile apps11331267Kimi K3
Design Arena: agents building Android appsNot measured1256Only Kimi K3 measured
Design Arena: agents building Godot gamesNot measured1223Only Kimi K3 measured
Design Arena: agents building gamesNot measured1252Only Kimi K3 measured
Design Arena: HTML slidesNot measured1256Only Kimi K3 measured
Design Arena: PowerPoint slidesNot measured1273Only Kimi K3 measured
Design Arena: spreadsheetsNot measured1058Only Kimi K3 measured
LiveBench research43.5%79.0%Kimi K3
LiveBench browser72.0%16.0%GPT-6 Luna
LiveBench long agentic48.1%42.8%GPT-6 Luna
SREBench (Vals AI)2.7%Not measuredOnly GPT-6 Luna measured
Finance Agent (Vals AI)49.9%53.1%Kimi K3
Tax Agent Bench (Vals AI)19.9%33.4%Kimi K3
Legal Research Bench (Vals AI)30.3%46.1%Kimi K3
Harvey's Legal Agent Benchmark (Vals AI)4.2%12.9%Kimi K3
Excel Modeling Benchmark (Vals AI)68.5%66.7%GPT-6 Luna
BioMysteryBench (Vals AI)61.5%72.6%Kimi K3
Terminal-Bench-Science (Vals AI)4.3%1.4%GPT-6 Luna
Vals Science Index28.4%Not measuredOnly GPT-6 Luna measured
Time Horizon Index (Vals AI)Not measured10.5%Only Kimi K3 measured
APEX-Agents44.3%47.8%Kimi K3
PostTrainBenchNot measured32.0%Only Kimi K3 measured
SpireClimb0.0%Not measuredOnly GPT-6 Luna measured
Vending-Bench 2Not measured$5,165Only Kimi K3 measured
Neither model has a result on the other 12 boards here
ReasoningLike-for-likePublic boards, shown as published, kept out of the index010
Reasoning benchmarks for GPT-6 Luna and Kimi K3
BenchmarkGPT-6 LunaKimi K3Leader
GPQA DiamondNot measured92.9%Only Kimi K3 measured
LiveBench reasoning81.8%90.7%Kimi K3
MysteryMechanism (Vals AI)19.4%Not measuredOnly GPT-6 Luna measured
MMMU Pro (Vals AI)Not measured88.2%Only Kimi K3 measured
GPQA Diamond (Artificial Analysis run)Not measured93.5%Only Kimi K3 measured
Humanity's Last Exam (Artificial Analysis run)38.5%46.9%Kimi K3
GPQA Diamond (Epoch AI run)90.5%93.1%Kimi K3
ARC-AGI86.7%94.5%Kimi K3
ARC-AGI-259.3%60.4%Kimi K3
SimpleBenchNot measured60.7%Only Kimi K3 measured
Chess puzzles36.0%37.0%Kimi K3
Mystery game puzzles7.0%26.0%Kimi K3
LMArena Text: hard prompts14101495Kimi K3
LMArena Text: expert14421520Kimi K3
LMArena Text: hard prompts in English14101496Kimi K3
LMArena Vision: diagrams1245Not measuredOnly GPT-6 Luna measured
LMArena Vision: homework1261Not measuredOnly GPT-6 Luna measured
Neither model has a result on the other 4 boards here
MathLike-for-likePublic boards, shown as published, kept out of the index33
Math benchmarks for GPT-6 Luna and Kimi K3
BenchmarkGPT-6 LunaKimi K3Leader
OTIS Mock AIME98.9%97.2%GPT-6 Luna
FrontierMath, tiers 1 to 378.9%72.2%GPT-6 Luna
FrontierMath, tier 456.1%39.0%GPT-6 Luna
ProofBench64.0%87.0%Kimi K3
LMArena Text: math14091494Kimi K3
LMArena Text: mathematical work14271505Kimi K3
Neither model has a result on the other 7 boards here
KnowledgeLike-for-likePublic boards, shown as published, kept out of the index06
Knowledge benchmarks for GPT-6 Luna and Kimi K3
BenchmarkGPT-6 LunaKimi K3Leader
MMLU ProNot measured88.0%Only Kimi K3 measured
LegalBench (Vals AI)Not measured86.2%Only Kimi K3 measured
CorpFin (Vals AI)Not measured71.6%Only Kimi K3 measured
TaxEval (Vals AI)Not measured75.7%Only Kimi K3 measured
MortgageTax (Vals AI)Not measured66.3%Only Kimi K3 measured
MedCode (Vals AI)44.7%49.4%Kimi K3
SimpleQA Verified41.4%50.6%Kimi K3
LMArena Text: science13861508Kimi K3
LMArena Text: medicine and healthcare13521489Kimi K3
LMArena Text: legal and government14001503Kimi K3
LMArena Text: business and finance13881470Kimi K3
Neither model has a result on the other 6 boards here
Web designLike-for-likePublic boards, shown as published, kept out of the index17
Web design benchmarks for GPT-6 Luna and Kimi K3
BenchmarkGPT-6 LunaKimi K3Leader
Design Arena: websites12721336Kimi K3
Design Arena: UI components12971345Kimi K3
Design Arena: game dev12591361Kimi K3
Design Arena: data viz12151350Kimi K3
Design Arena: 3D12171388Kimi K3
Design Arena: all code categories12711361Kimi K3
Design Arena: SVG12531301Kimi K3
Design Arena: ASCII art1156Not measuredOnly GPT-6 Luna measured
LiveBench design82.5%77.2%GPT-6 Luna
GeneralLike-for-likePublic boards, shown as published, kept out of the index125
General benchmarks for GPT-6 Luna and Kimi K3
BenchmarkGPT-6 LunaKimi K3Leader
Vals Index52.3%53.0%Kimi K3
LiveBench data analysis73.4%78.7%Kimi K3
Public Benefits Bench (Vals AI)57.6%68.2%Kimi K3
SAGE (Vals AI)48.1%52.8%Kimi K3
MedScribe (Vals AI)83.7%88.0%Kimi K3
Vals Multimodal IndexNot measured73.4%Only Kimi K3 measured
Long context reasoning (AA-LCR)83.3%88.7%Kimi K3
DTBench90.1%91.2%Kimi K3
LMCA44.5%52.7%Kimi K3
Surface Evolver BenchNot measured95.0%Only Kimi K3 measured
Furniture assembly44.2%34.2%GPT-6 Luna
LMArena Text13891476Kimi K3
LMArena Text: instruction following14081485Kimi K3
LMArena Text: creative writing13631457Kimi K3
LMArena Vision1216Not measuredOnly GPT-6 Luna measured
LMArena Text: English13931481Kimi K3
LMArena Text: non-English13811466Kimi K3
LMArena Text: Chinese14271529Kimi K3
LMArena Text: German13761490Kimi K3
LMArena Text: Japanese13691494Kimi K3
LMArena Text: Korean13591460Kimi K3
LMArena Text: French14081492Kimi K3
LMArena Text: Spanish13911472Kimi K3
LMArena Text: Russian13921485Kimi K3
LMArena Text: Polish13831458Kimi K3
LMArena Text: multi-turn13921489Kimi K3
LMArena Text: longer queries14081494Kimi K3
LMArena Text: writing and language13841471Kimi K3
LMArena Text: entertainment and media13641453Kimi K3
LMArena Vision: English1204Not measuredOnly GPT-6 Luna measured
LMArena Vision: Chinese1266Not measuredOnly GPT-6 Luna measured
LMArena Vision: reading text1225Not measuredOnly GPT-6 Luna measured
LMArena Vision: creative writing1205Not measuredOnly GPT-6 Luna measured
Neither model has a result on the other 13 boards here
Image generationNot comparablePublic boards, shown as published, kept out of the index0 boards, none shared
Image generation benchmarks for GPT-6 Luna and Kimi K3
BenchmarkGPT-6 LunaKimi K3Leader
Neither model has a result on 5 boards here

What each workload costs

Three fixed token mixes at each model's listed price, so per-token rates become a bill.

Chat turn

1K input + 500 output tokens

GPT-6 Luna$0.0003Fits in one request
Kimi K3$0.0062Fits in one request

GPT-6 Luna costs less

Repository review

50K input + 3K output tokens

GPT-6 Luna$0.0065Fits in one request
Kimi K3$0.048Fits in one request

GPT-6 Luna costs less

Agent loop

200K input + 10K output tokens

GPT-6 Luna$0.025Fits in one request
Kimi K3$0.167Fits in one request

GPT-6 Luna costs less

Listed OpenRouter rates, without cache or batch discounts. A workload that does not fit a model's context window would need splitting.

Specification differences

The leading value in a row is marked; a row with a missing value names no leader. Our two rows are marked in red.

Specifications of GPT-6 Luna and Kimi K3
SpecificationOpenAI GPT-6 LunaMoonshotAI Kimi K3
MakerOpenAIMoonshot AI
WeightsNo public weights listedOpen weights
ReleasedSeptember 22, 2026July 16, 2026
Context window1.05M1.05M
Input $/Mtok$0.10$0.239
Output $/Mtok$0.50$11.936
Coding index71.461.8
Independent measurements behind it22
Cost per solved taskNot computable$0.81
SourceOpenRouter listingOpenRouter listing

Questions

Is GPT-6 Luna better than Kimi K3 for coding?

Pick GPT-6 Luna for coding: it scores 71.4 on the Vibe Coding Index against 61.8 for Kimi K3. Pick Kimi K3 when what matters is LMArena WebDev or Terminal-Bench 4 (Vals AI), where it leads.

Which is cheaper, GPT-6 Luna or Kimi K3?

GPT-6 Luna costs $0.10 per million input tokens and $0.50 per million output tokens; Kimi K3 costs $0.239 and $11.936. Cost per solved task is known for Kimi K3 only.

Which has the bigger context window, GPT-6 Luna or Kimi K3?

GPT-6 Luna, with 1.05M tokens against 1.05M.

How many benchmarks is the GPT-6 Luna vs Kimi K3 comparison based on?

90 benchmarks have a result for both models as of October 21, 2026. GPT-6 Luna's coding index rests on 2 independent benchmarks and Kimi K3's on 2. Where only one model has a result, the page says so instead of naming a winner.

Compare next

Embed this comparison on your site

Free under CC BY 4.0, while the source link stays visible. Preview the frame · Terms and other embeds

<iframe src="https://llmbenchmark.ai/embed/compare/gpt-6-luna-vs-kimi-k3" title="GPT-6 Luna vs Kimi K3, LLMBenchmark.ai" width="100%" height="360" style="border:0;max-width:100%" loading="lazy"></iframe>
<p style="font:13px/1.4 sans-serif;margin:6px 0 0">Source: <a href="https://llmbenchmark.ai/compare/gpt-6-luna-vs-kimi-k3">LLMBenchmark.ai, GPT-6 Luna vs Kimi K3</a></p>