Head-to-head comparison

GPT-5.6 Luna vs. Kimi K3

Compare published benchmark results from matching versions and cohorts, API pricing, and technical specifications. Any documented test setup differences remain visible.

shared result series: 195
distinct benchmarks: 26
latest retrieval: 2026-09-04

First modelSecond model

Specifications

General specifications

Release date, availability, context window, architecture, and published parameter counts at a glance. Undisclosed details remain marked as unavailable.

Specifications for GPT-5.6 Luna and Kimi K3
Attribute	GPT-5.6 Luna	Kimi K3
Provider	OpenAI	Moonshot AI
Released	Jun 26, 2026	Jul 16, 2026
Availability	Active	Active
Model type	Proprietary	Open Weights
Parameters	Not published	2.8T, 104B active
Architecture	Not published	Mixture of Experts
Context window	1,050,000 tokens	1,048,576 tokens
Knowledge cutoff	February 16, 2026	Not published
Technical sources	Model, Context, Knowledge cutoff	Model

Pricing

API pricing compared

The table compares official standard API rates per 1M tokens, including published cache pricing. Batch, fast, priority, regional surcharges, tool calls, and cloud platform pricing are excluded.

API pricing for GPT-5.6 Luna and Kimi K3
Price type	GPT-5.6 Luna	Kimi K3
API input	$0.2 ≤272K / $0.4 >272K	$3
API output	$1.2 ≤272K / $1.8 >272K	$15
Cache read	$0.02 ≤272K / $0.04 >272K	$0.3
Cache write (5 min.)	$0.25 ≤272K / $0.5 >272K	Not listed
Cache write (1 hr.)	Not listed	Not listed
Price verified	08/11/2026 Source	07/30/2026 Source

GPT-5.6 LunaKimi K3

API inputUSD per 1M tokens, base tier

GPT-5.6 Luna$0.2

Kimi K3$3

API outputUSD per 1M tokens, base tier

GPT-5.6 Luna$1.2

Kimi K3$15

Cache readUSD per 1M tokens, base tier

GPT-5.6 Luna$0.02

Kimi K3$0.3

Key to the marks:better valuebetter, but not conclusivetie

Pricing by provider

Direct developer pricing and provider endpoint tariffs routed through OpenRouter are listed separately. Prices are in USD per 1M tokens. Context-dependent direct tiers plus regional, Flex, Priority, and other OpenRouter tariffs remain individually identifiable.

Provider pricing for GPT-5.6 Luna and Kimi K3
Model	Provider	Purchase route and tariff	Input per 1M tokens	Output per 1M tokens	Source
GPT-5.6 Luna	OpenAI	Direct from developerUp to 272,000 context tokens	$0.2	$1.2	Source08/11/2026
	OpenAI	Direct from developerAbove 272,000 context tokens	$0.4	$1.8	Source08/11/2026
	Amazon Bedrock	Via OpenRouteramazon-bedrock/us-east-1	$0.22	$1.32	Source09/07/2026
	Azure	Via OpenRouterazure	$0.2	$1.2	Source09/07/2026
	Azure	Via OpenRouterazure/eu	$0.22	$1.32	Source09/07/2026
	Azure	Via OpenRouterazure/us	$0.22	$1.32	Source09/07/2026
	OpenAI	Via OpenRouteropenai	$0.2	$1.2	Source09/07/2026
	OpenAI	Via OpenRouteropenai/fast	$0.4	$2.4	Source09/07/2026
	OpenAI	Via OpenRouteropenai/flex	Lowest listed price: $0.1	Lowest listed price: $0.6	Source09/07/2026
Kimi K3	Moonshot AI	Direct from developerStandard API	$3	$15	Source07/30/2026
	Alibaba	Via OpenRouteralibaba	$3.45	$17.25	Source09/07/2026
	BaseTen	Via OpenRouterbaseten/fp8	$3	$15	Source09/07/2026
	Chutes	Via OpenRouterchutes/mxfp4	$3	$15	Source09/07/2026
	DeepInfra	Via OpenRouterdeepinfra/bf16	$2.85	$14.25	Source09/07/2026
	DigitalOcean	Via OpenRouterdigitalocean	$2.85	$14.25	Source09/07/2026
	Fireworks	Via OpenRouterfireworks	$3	$15	Source09/07/2026
	Fireworks	Via OpenRouterfireworks/fast	$4.5	$22.5	Source09/07/2026
	Fireworks	Via OpenRouterfireworks/us	$3.3	$16.5	Source09/07/2026
	Makora	Via OpenRoutermakora	Lowest listed price: $2.55	Lowest listed price: $12.75	Source09/07/2026
	Modal	Via OpenRoutermodal/mxfp4	$3	$15	Source09/07/2026
	Moonshot AI	Via OpenRoutermoonshotai/mxfp4	$3	$15	Source09/07/2026
	Morph	Via OpenRoutermorph/fast	$6	$22.5	Source09/07/2026
	Morph	Via OpenRoutermorph/fp4	$2.6	$14	Source09/07/2026
	Parasail	Via OpenRouterparasail/fp4	$3	$15	Source09/07/2026
	Phala	Via OpenRouterphala	$3	$15	Source09/07/2026
	Sail Research	Via OpenRoutersail-research/fp4	$2.6	$13	Source09/07/2026
	Together	Via OpenRoutertogether	$3	$15	Source09/07/2026
	Wafer	Via OpenRouterwafer	$3	Lowest listed price: $12.75	Source09/07/2026

Performance

Shared benchmarks

Only published results with the same benchmark version, task, metric, and comparison cohort are paired. Different reasoning levels, agents, harnesses, or output limits appear directly in the table.

Capability profile from matched benchmarks

Each axis averages directly matched benchmark families. A value of 100 means the stronger value within this pair, not a universal quality score.

GPT-5.6 Luna

Kimi K3

Coding: 72.6 / 84 (4 benchmark families)

Reasoning: 98.6 / 100 (1 benchmark family)

Mathematics: 69 / 100 (1 benchmark family)

Knowledge: 97.8 / 100 (1 benchmark family)

Finance: 97.9 / 99.1 (5 benchmark families)

Legal: 63.9 / 100 (3 benchmark families)

Agentic tasks: 97.7 / 100 (1 benchmark family)

Multimodal: 96.5 / 100 (1 benchmark family)

27 matched rows from 25 benchmark families were considered. The radar shows 8 of 13 comparable categories.

GPT-5.6 LunaKimi K3

BioMysteryBenchOverall. Higher is better. No documented setup difference

GPT-5.6 Luna61.481 %

Kimi K371.481 %

Code MigrationOverall. Higher is better. No documented setup difference

GPT-5.6 Luna44.55 %

Kimi K316.099 %

CorpFin v2Overall. Higher is better. No documented setup difference

GPT-5.6 Luna64.219 %

Kimi K371.562 %

CyberBenchOverall. Higher is better. No documented setup difference

GPT-5.6 Luna83.898 %

Kimi K379.026 %

EMBOverall. Higher is better. No documented setup difference

GPT-5.6 Luna67.116 %

Kimi K366.399 %

Finance Agent (v2)Overall. Higher is better. No documented setup difference

GPT-5.6 Luna55.044 %

Kimi K354.36 %

GPQA DiamondOverall. Higher is better. No documented setup difference

GPT-5.6 Luna91.666 %

Kimi K392.929 %

Harvey's Legal Agent BenchmarkOverall · Task fully resolved. Higher is better. No documented setup difference

GPT-5.6 Luna1.25 %

Kimi K310.833 %

Legal Research BenchOverall · All-pass. Higher is better. No documented setup difference

GPT-5.6 Luna36.538 %

Kimi K344.231 %

LegalBenchOverall. Higher is better. No documented setup difference

GPT-5.6 Luna84.034 %

Kimi K386.016 %

LMArena Text, Style ControlOverall. Higher is better. Test setup not documented as identical

GPT-5.6 Luna1,452.364

Kimi K31,489.017

MedCodeOverall. Higher is better. No documented setup difference

GPT-5.6 Luna42.391 %

Kimi K348.884 %

Key to the marks:better valuebetter, but not conclusivetie

Benchmark scores for GPT-5.6 Luna and Kimi K3
Benchmark and task	GPT-5.6 Luna	Kimi K3	Source
BioMysteryBenchOverall Test details No documented difference in the test setupVersion: 1Metric: accuracyScoring: Higher is betterSettings: Harness: Terminus 2	61.481 %	Winner71.481 %	Vals AI Source details Data as of: 09/02/2026
Code MigrationOverall Test details No documented difference in the test setupVersion: 1Metric: accuracyScoring: Higher is better	Winner44.55 %	16.099 %	Vals AI Source details Data as of: 09/03/2026
CorpFin v2Overall Test details No documented difference in the test setupVersion: 2Metric: accuracyScoring: Higher is better	64.219 %	Winner71.562 %	Vals AI Source details Data as of: 08/12/2026
CyberBenchOverall Test details No documented difference in the test setupVersion: 1Metric: accuracyScoring: Higher is better	Winner83.898 %	79.026 %	Vals AI Source details Data as of: 09/01/2026
EMBOverall Test details No documented difference in the test setupVersion: 1Metric: accuracyScoring: Higher is better	Winner67.116 %	66.399 %	Vals AI Source details Data as of: 09/03/2026
Finance Agent (v2)Overall Test details No documented difference in the test setupVersion: 2Metric: accuracyScoring: Higher is better	Winner55.044 %	54.36 %	Vals AI Source details Data as of: 09/03/2026
GPQA DiamondOverall Test details No documented difference in the test setupVersion: 1Metric: accuracyScoring: Higher is better	91.666 %	Winner92.929 %	Vals AI Source details Data as of: 09/01/2026
Harvey's Legal Agent BenchmarkOverall · Task fully resolved Test details No documented difference in the test setupVersion: 1Metric: task resolution rateScoring: Higher is better	1.25 %	Winner10.833 %	Vals AI Source details Data as of: 09/03/2026
Legal Research BenchOverall · All-pass Test details No documented difference in the test setupVersion: 1Metric: all-pass rateScoring: Higher is better	36.538 %	Winner44.231 %	Vals AI Source details Data as of: 09/03/2026
LegalBenchOverall Test details No documented difference in the test setupVersion: 1Metric: accuracyScoring: Higher is better	84.034 %	Winner86.016 %	Vals AI Source details Data as of: 09/01/2026
LMArena Text, Style ControlOverall Test details Test setup not documented as identicalNo direct winnerVersion: style-control-v1Metric: style-controlled Bradley-Terry ratingScoring: Higher is betterGPT-5.6 Luna: Snapshot: gpt-5.6-luna-xhigh, Reasoning: xhigh, Harness: Arena text, style control Kimi K3: Snapshot: kimi-k3-max, Reasoning: max, Harness: Arena text, style controlGPT-5.6 Luna: Style-controlled Arena rating from 24,433 anonymous pairwise votes.Kimi K3: Style-controlled Arena rating from 17,895 anonymous pairwise votes.	1,452.364 95% confidence interval: ±5.03The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.	Higher measured value1,489.017 95% confidence interval: ±5.47The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.	LMArena Source details Data as of: 09/01/2026
MedCodeOverall Test details No documented difference in the test setupVersion: 1Metric: accuracyScoring: Higher is better	42.391 %	Winner48.884 %	Vals AI Source details Data as of: 09/03/2026
MedScribeOverall Test details No documented difference in the test setupVersion: 1Metric: accuracyScoring: Higher is better	84.391 %	Winner87.958 %	Vals AI Source details Data as of: 09/03/2026
MMLU-ProOverall Test details No documented difference in the test setupVersion: 1Metric: accuracyScoring: Higher is better	86.036 %	Winner87.973 %	Vals AI Source details Data as of: 09/01/2026
MMMU-ProOverall Test details No documented difference in the test setupVersion: 1Metric: accuracyScoring: Higher is better	85.029 %	Winner88.15 %	Vals AI Source details Data as of: 09/01/2026
MortgageTaxOverall Test details No documented difference in the test setupVersion: 1Metric: accuracyScoring: Higher is better	Winner67.29 %	66.336 %	Vals AI Source details Data as of: 09/01/2026
ProgramBenchOverall Test details No documented difference in the test setupVersion: 1Metric: accuracyScoring: Higher is better	0 %	Winner2 %	Vals AI Source details Data as of: 09/01/2026
ProofBenchOverall Test details No documented difference in the test setupVersion: 1.1Metric: accuracyScoring: Higher is better	60 %	Winner87 %	Vals AI Source details Data as of: 09/01/2026
Public Benefits Bench v1.1Overall Test details No documented difference in the test setupVersion: 1.1Metric: accuracyScoring: Higher is better	61.164 %	Winner68.268 %	Vals AI Source details Data as of: 09/01/2026
SAGEOverall Test details No documented difference in the test setupVersion: 1Metric: accuracyScoring: Higher is better	44.22 %	Winner54.26 %	Vals AI Source details Data as of: 09/03/2026
SWE-bench VerifiedOverall Test details No documented difference in the test setupVersion: 1Metric: accuracyScoring: Higher is better	93 %	Winner93.4 %	Vals AI Source details Data as of: 09/01/2026
TaxEval v2Overall Test details No documented difference in the test setupVersion: 2Metric: accuracyScoring: Higher is better	Winner76.166 %	75.716 %	Vals AI Source details Data as of: 09/01/2026
Terminal-Bench 2.1Overall Test details No documented difference in the test setupVersion: 2.1Metric: accuracyScoring: Higher is better	79.026 %	Winner80.899 %	Vals AI Source details Data as of: 09/03/2026
Vals IndexOverall Test details No documented difference in the test setupVersion: 2Metric: weighted index scoreScoring: Higher is better	Winner59.881 %	57.813 %	Vals AI Source details Data as of: 09/03/2026
Vals Multimodal IndexOverall Test details No documented difference in the test setupVersion: 1.2Metric: weighted index scoreScoring: Higher is better	69.058 %	Winner73.42 %	Vals AI Source details Data as of: 08/11/2026
Vibe Code Bench v1.1Overall Test details No documented difference in the test setupVersion: 1.1Metric: accuracyScoring: Higher is betterSettings: Harness: OpenHands	77.055 %	Winner84.963 %	Vals AI Source details Data as of: 09/03/2026
CorpFin v2Exact Pages Test details Test setup not documented as identicalNo direct winnerVersion: 2Metric: accuracyScoring: Higher is betterGPT-5.6 Luna: Reasoning: max, Output limit: 128,000 tokens Kimi K3: Temperature: 1, Output limit: 262,144 tokens	63.52 %	Higher measured value69.347 %	Vals AI Source details Data as of: 08/06/2026
CyberBenchPatch Test details Test setup not documented as identicalNo direct winnerVersion: 1Metric: accuracyScoring: Higher is betterKimi K3: Temperature: 1, Output limit: 262,144 tokens	79.661 %	Higher measured value83.051 %	Vals AI Source details Data as of: 08/03/2026
EMBComps Test details Test setup not documented as identicalNo direct winnerVersion: 1Metric: accuracyScoring: Higher is betterGPT-5.6 Luna: Reasoning: max, Output limit: 128,000 tokens Kimi K3: Temperature: 1, Output limit: 262,144 tokens	54.573 %	Higher measured value72.685 %	Vals AI Source details Data as of: 08/06/2026
Finance Agent (v2)Adjustments Test details Test setup not documented as identicalNo direct winnerVersion: 2Metric: accuracyScoring: Higher is betterGPT-5.6 Luna: Reasoning: max, Output limit: 128,000 tokens Kimi K3: Temperature: 1, Output limit: 262,144 tokens	Higher measured value52.027 %	51.461 %	Vals AI Source details Data as of: 08/06/2026
GPQA DiamondFew-Shot CoT Test details Test setup not documented as identicalNo direct winnerVersion: 1Metric: accuracyScoring: Higher is betterGPT-5.6 Luna: Reasoning: max, Output limit: 128,000 tokens Kimi K3: Temperature: 1, Output limit: 262,144 tokens	92.424 %	Higher measured value93.434 %	Vals AI Source details Data as of: 08/09/2026
Harvey's Legal Agent BenchmarkAntitrust Competition · Criteria passed Test details Test setup not documented as identicalNo direct winnerVersion: 1Metric: criteria pass rateScoring: Higher is betterGPT-5.6 Luna: Reasoning: max, Output limit: 128,000 tokens Kimi K3: Temperature: 1, Output limit: 262,144 tokens	85.145 %	Higher measured value87.319 %	Vals AI Source details Data as of: 08/07/2026
Legal Research BenchAdministrative / Regulatory · All-pass Test details Test setup not documented as identicalNo direct winnerVersion: 1Metric: all-pass rateScoring: Higher is betterGPT-5.6 Luna: Reasoning: max, Output limit: 128,000 tokens Kimi K3: Temperature: 1, Output limit: 262,144 tokens	48.485 %	Higher measured value54.545 %	Vals AI Source details Data as of: 08/06/2026
LegalBenchConclusion Tasks Test details Test setup not documented as identicalNo direct winnerVersion: 1Metric: accuracyScoring: Higher is betterGPT-5.6 Luna: Reasoning: max, Output limit: 128,000 tokens Kimi K3: Temperature: 1, Output limit: 262,144 tokens	88.864 %	Higher measured value90.733 %	Vals AI Source details Data as of: 08/09/2026
LMArena Text, Style ControlBusiness, management and finance Test details Test setup not documented as identicalNo direct winnerVersion: style-control-v1Metric: style-controlled Bradley-Terry ratingScoring: Higher is betterGPT-5.6 Luna: Snapshot: gpt-5.6-luna-xhigh, Reasoning: xhigh, Harness: Arena text, style control Kimi K3: Snapshot: kimi-k3-max, Reasoning: max, Harness: Arena text, style controlGPT-5.6 Luna: Style-controlled Arena rating from 4,691 anonymous pairwise votes.Kimi K3: Style-controlled Arena rating from 3,520 anonymous pairwise votes.	1,461.709 95% confidence interval: ±9.371The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.	Higher measured value1,489.216 95% confidence interval: ±10.41The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.	LMArena Source details Data as of: 09/01/2026
MMLU-ProBiology Test details Test setup not documented as identicalNo direct winnerVersion: 1Metric: accuracyScoring: Higher is betterGPT-5.6 Luna: Reasoning: max, Output limit: 128,000 tokens Kimi K3: Temperature: 1, Output limit: 262,144 tokens	93.305 %	Higher measured value93.863 %	Vals AI Source details Data as of: 08/09/2026
MortgageTaxNumerical Extraction Test details Test setup not documented as identicalNo direct winnerVersion: 1Metric: accuracyScoring: Higher is betterGPT-5.6 Luna: Reasoning: max, Output limit: 128,000 tokens Kimi K3: Temperature: 1, Output limit: 262,144 tokens	75.596 %	Higher measured value78.855 %	Vals AI Source details Data as of: 08/09/2026
ProgramBenchAlmost Resolved Test details Test setup not documented as identicalNo direct winnerVersion: 1Metric: accuracyScoring: Higher is betterGPT-5.6 Luna: Reasoning: max, Output limit: 128,000 tokens Kimi K3: Temperature: 1, Output limit: 262,144 tokens	9 %	Higher measured value17.5 %	Vals AI Source details Data as of: 08/09/2026
SAGEAutomata Test details Test setup not documented as identicalNo direct winnerVersion: 1Metric: accuracyScoring: Higher is betterGPT-5.6 Luna: Reasoning: max, Output limit: 30,000 tokens Kimi K3: Temperature: 1, Output limit: 30,000 tokens	31.35 %	Higher measured value44.048 %	Vals AI Source details Data as of: 08/09/2026
SWE-bench Verified<15 min fix Test details Test setup not documented as identicalNo direct winnerVersion: 1Metric: accuracyScoring: Higher is betterGPT-5.6 Luna: Reasoning: max, Output limit: 128,000 tokens Kimi K3: Temperature: 1, Output limit: 262,144 tokens	Higher measured value96.392 %	92.268 %	Vals AI Source details Data as of: 08/08/2026
TaxEval v2Correctness Test details Test setup not documented as identicalNo direct winnerVersion: 2Metric: accuracyScoring: Higher is betterGPT-5.6 Luna: Reasoning: max, Output limit: 128,000 tokens Kimi K3: Temperature: 1, Output limit: 262,144 tokens	Higher measured value66.558 %	65.331 %	Vals AI Source details Data as of: 08/09/2026
Terminal-Bench 2.1Easy Test details Test setup not documented as identicalNo direct winnerVersion: 2.1Metric: accuracyScoring: Higher is betterGPT-5.6 Luna: Reasoning: max, Output limit: 128,000 tokens Kimi K3: Temperature: 1, Output limit: 262,144 tokens	83.333 %	Higher measured value91.667 %	Vals AI Source details Data as of: 08/06/2026
Vals IndexCorpFin v2 Test details Test setup not documented as identicalNo direct winnerVersion: 1.2Metric: benchmark scoreScoring: Higher is betterGPT-5.6 Luna: Reasoning: max, Output limit: 128,000 tokens Kimi K3: Temperature: 1, Output limit: 262,144 tokens	65.035 %	Higher measured value72.611 %	Vals AI Source details Data as of: 08/09/2026
Vals Multimodal IndexCorpFin v2 Test details Test setup not documented as identicalNo direct winnerVersion: 1.2Metric: benchmark scoreScoring: Higher is betterGPT-5.6 Luna: Reasoning: max, Output limit: 128,000 tokens Kimi K3: Temperature: 1, Output limit: 262,144 tokens	65.035 %	Higher measured value72.611 %	Vals AI Source details Data as of: 08/09/2026
CorpFin v2Max Fitting Context Test details Test setup not documented as identicalNo direct winnerVersion: 2Metric: accuracyScoring: Higher is betterGPT-5.6 Luna: Reasoning: max, Output limit: 128,000 tokens Kimi K3: Temperature: 1, Output limit: 262,144 tokens	64.103 %	Higher measured value72.727 %	Vals AI Source details Data as of: 08/06/2026
CyberBenchPoC Test details Test setup not documented as identicalNo direct winnerVersion: 1Metric: accuracyScoring: Higher is betterKimi K3: Temperature: 1, Output limit: 262,144 tokens	Higher measured value88.136 %	75 %	Vals AI Source details Data as of: 08/03/2026
EMBDataroom Test details Test setup not documented as identicalNo direct winnerVersion: 1Metric: accuracyScoring: Higher is betterGPT-5.6 Luna: Reasoning: max, Output limit: 128,000 tokens Kimi K3: Temperature: 1, Output limit: 262,144 tokens	83.009 %	Higher measured value85.13 %	Vals AI Source details Data as of: 08/06/2026
Finance Agent (v2)All-Pass Test details Test setup not documented as identicalNo direct winnerVersion: 2Metric: accuracyScoring: Higher is betterGPT-5.6 Luna: Reasoning: max, Output limit: 128,000 tokens Kimi K3: Temperature: 1, Output limit: 262,144 tokens	Higher measured value43.285 %	41.69 %	Vals AI Source details Data as of: 08/06/2026
GPQA DiamondZero-Shot CoT Test details Test setup not documented as identicalNo direct winnerVersion: 1Metric: accuracyScoring: Higher is betterGPT-5.6 Luna: Reasoning: max, Output limit: 128,000 tokens Kimi K3: Temperature: 1, Output limit: 262,144 tokens	90.909 %	Higher measured value92.424 %	Vals AI Source details Data as of: 08/09/2026
Harvey's Legal Agent BenchmarkAntitrust Competition · Task fully resolved Test details Test setup not documented as identicalNo direct winnerVersion: 1Metric: task resolution rateScoring: Higher is betterGPT-5.6 Luna: Reasoning: max, Output limit: 128,000 tokens Kimi K3: Temperature: 1, Output limit: 262,144 tokens	No direct winner0 %	No direct winner0 %	Vals AI Source details Data as of: 08/07/2026
Legal Research BenchAdministrative / Regulatory · Weighted partial credit Test details Test setup not documented as identicalNo direct winnerVersion: 1Metric: weighted partial-credit scoreScoring: Higher is betterGPT-5.6 Luna: Reasoning: max, Output limit: 128,000 tokens Kimi K3: Temperature: 1, Output limit: 262,144 tokens	87.513 %	Higher measured value90.731 %	Vals AI Source details Data as of: 08/06/2026
LegalBenchInterpretation Tasks Test details Test setup not documented as identicalNo direct winnerVersion: 1Metric: accuracyScoring: Higher is betterGPT-5.6 Luna: Reasoning: max, Output limit: 128,000 tokens Kimi K3: Temperature: 1, Output limit: 262,144 tokens	82.142 %	Higher measured value82.612 %	Vals AI Source details Data as of: 08/09/2026
LMArena Text, Style ControlChinese Test details Test setup not documented as identicalNo direct winnerVersion: style-control-v1Metric: style-controlled Bradley-Terry ratingScoring: Higher is betterGPT-5.6 Luna: Snapshot: gpt-5.6-luna-xhigh, Reasoning: xhigh, Harness: Arena text, style control Kimi K3: Snapshot: kimi-k3-max, Reasoning: max, Harness: Arena text, style controlGPT-5.6 Luna: Style-controlled Arena rating from 1,691 anonymous pairwise votes.Kimi K3: Style-controlled Arena rating from 1,168 anonymous pairwise votes.	1,474.185 95% confidence interval: ±15.484The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.	Higher measured value1,528.536 95% confidence interval: ±17.657The Arena score measures human preference rather than a fixed capability test. The confidence interval and model configuration are part of the result.	LMArena Source details Data as of: 09/01/2026
MMLU-ProBusiness Test details Test setup not documented as identicalNo direct winnerVersion: 1Metric: accuracyScoring: Higher is betterGPT-5.6 Luna: Reasoning: max, Output limit: 128,000 tokens Kimi K3: Temperature: 1, Output limit: 262,144 tokens	91.001 %	Higher measured value92.015 %	Vals AI Source details Data as of: 08/09/2026
MortgageTaxSemantic Extraction Test details Test setup not documented as identicalNo direct winnerVersion: 1Metric: accuracyScoring: Higher is betterGPT-5.6 Luna: Reasoning: max, Output limit: 128,000 tokens Kimi K3: Temperature: 1, Output limit: 262,144 tokens	Higher measured value58.983 %	53.816 %	Vals AI Source details Data as of: 08/09/2026
ProgramBenchFully Resolved Test details Test setup not documented as identicalNo direct winnerVersion: 1Metric: accuracyScoring: Higher is betterGPT-5.6 Luna: Reasoning: max, Output limit: 128,000 tokens Kimi K3: Temperature: 1, Output limit: 262,144 tokens	0 %	Higher measured value2 %	Vals AI Source details Data as of: 08/09/2026
SAGECalculus Test details Test setup not documented as identicalNo direct winnerVersion: 1Metric: accuracyScoring: Higher is betterGPT-5.6 Luna: Reasoning: max, Output limit: 30,000 tokens Kimi K3: Temperature: 1, Output limit: 30,000 tokens	64.506 %	Higher measured value75.617 %	Vals AI Source details Data as of: 08/09/2026
SWE-bench Verified>4 hours Test details Test setup not documented as identicalNo direct winnerVersion: 1Metric: accuracyScoring: Higher is betterGPT-5.6 Luna: Reasoning: max, Output limit: 128,000 tokens Kimi K3: Temperature: 1, Output limit: 262,144 tokens	No direct winner66.667 %	No direct winner66.667 %	Vals AI Source details Data as of: 08/08/2026
TaxEval v2Stepwise Reasoning Test details Test setup not documented as identicalNo direct winnerVersion: 2Metric: accuracyScoring: Higher is betterGPT-5.6 Luna: Reasoning: max, Output limit: 128,000 tokens Kimi K3: Temperature: 1, Output limit: 262,144 tokens	85.773 %	Higher measured value86.1 %	Vals AI Source details Data as of: 08/09/2026
Terminal-Bench 2.1Hard Test details Test setup not documented as identicalNo direct winnerVersion: 2.1Metric: accuracyScoring: Higher is betterGPT-5.6 Luna: Reasoning: max, Output limit: 128,000 tokens Kimi K3: Temperature: 1, Output limit: 262,144 tokens	70 %	Higher measured value74.444 %	Vals AI Source details Data as of: 08/06/2026
Vals IndexFinance Agent v2 Test details Test setup not documented as identicalNo direct winnerVersion: 1.2Metric: benchmark scoreScoring: Higher is betterGPT-5.6 Luna: Reasoning: max, Output limit: 128,000 tokens Kimi K3: Temperature: 1, Output limit: 262,144 tokens	55.555 %	Higher measured value55.882 %	Vals AI Source details Data as of: 08/09/2026
Vals Multimodal IndexFinance Agent v2 Test details Test setup not documented as identicalNo direct winnerVersion: 1.2Metric: benchmark scoreScoring: Higher is betterGPT-5.6 Luna: Reasoning: max, Output limit: 128,000 tokens Kimi K3: Temperature: 1, Output limit: 262,144 tokens	55.555 %	Higher measured value55.882 %	Vals AI Source details Data as of: 08/09/2026
CorpFin v2Shared Max Context Test details Test setup not documented as identicalNo direct winnerVersion: 2Metric: accuracyScoring: Higher is betterGPT-5.6 Luna: Reasoning: max, Output limit: 128,000 tokens Kimi K3: Temperature: 1, Output limit: 262,144 tokens	65.035 %	Higher measured value72.611 %	Vals AI Source details Data as of: 08/06/2026
EMBDCF Test details Test setup not documented as identicalNo direct winnerVersion: 1Metric: accuracyScoring: Higher is betterGPT-5.6 Luna: Reasoning: max, Output limit: 128,000 tokens Kimi K3: Temperature: 1, Output limit: 262,144 tokens	Higher measured value60.482 %	58.877 %	Vals AI Source details Data as of: 08/06/2026
Key to the marks:better valuebetter, but not conclusivetie

How to read this comparison

Winning one benchmark is not an overall verdict

Your workload, budget, and required context length matter most. A coding benchmark says little about visual understanding or agent performance.

The standard price table uses direct developer rates. The provider comparison labels OpenRouter endpoints, regions, and special tariffs separately.

Every result links to its measurement source and retrieval date. Labels distinguish vendor reports, official benchmark leaderboards, and independent evaluations. Disputed or archived results are excluded.

More matchups

Compare GPT-5.6 Luna and Kimi K3 with other leading models using the same data and benchmark logic.

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