Head-to-head comparison

GPT-6 Astra 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: 11
distinct benchmarks: 11
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-6 Astra and Kimi K3
Attribute	GPT-6 Astra	Kimi K3
Provider	OpenAI	Moonshot AI
Released	Sep 3, 2026	Jul 16, 2026
Availability	Limited access	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	April 30, 2026	Not published
Technical sources	Model, Context	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-6 Astra and Kimi K3
Price type	GPT-6 Astra	Kimi K3
API input	$10 ≤272K / $20 >272K	$3
API output	$50 ≤272K / $75 >272K	$15
Cache read	$1 ≤272K / $2 >272K	$0.3
Cache write (5 min.)	$12.5 ≤272K / $25 >272K	Not listed
Cache write (1 hr.)	Not listed	Not listed
Price verified	09/04/2026 Source	07/30/2026 Source

GPT-6 AstraKimi K3

API inputUSD per 1M tokens, base tier

GPT-6 Astra$10

Kimi K3$3

API outputUSD per 1M tokens, base tier

GPT-6 Astra$50

Kimi K3$15

Cache readUSD per 1M tokens, base tier

GPT-6 Astra$1

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.

No provider tariff for GPT-6 Astra is available in the stored OpenRouter snapshot. The official direct price is still shown.

Provider pricing for GPT-6 Astra and Kimi K3
Model	Provider	Purchase route and tariff	Input per 1M tokens	Output per 1M tokens	Source
GPT-6 Astra	OpenAI	Direct from developerUp to 272,000 context tokens	Lowest listed price: $10	Lowest listed price: $50	Source09/04/2026
GPT-6 Astra	OpenAI	Direct from developerAbove 272,000 context tokens	$20	$75	Source09/04/2026
Kimi K3	Moonshot AI	Direct from developerStandard API	$3	$15	Source07/30/2026
	Alibaba	Via OpenRouteralibaba	$3.45	$17.25	Source09/04/2026
	BaseTen	Via OpenRouterbaseten/fp8	$3	$15	Source09/04/2026
	Chutes	Via OpenRouterchutes/mxfp4	$3	$15	Source09/04/2026
	DeepInfra	Via OpenRouterdeepinfra/bf16	$2.85	$14.25	Source09/04/2026
	DigitalOcean	Via OpenRouterdigitalocean	$2.85	$14.25	Source09/04/2026
	Fireworks	Via OpenRouterfireworks	$3	$15	Source09/04/2026
	Fireworks	Via OpenRouterfireworks/fast	$4.5	$22.5	Source09/04/2026
	Fireworks	Via OpenRouterfireworks/us	$3.3	$16.5	Source09/04/2026
	Makora	Via OpenRoutermakora	$2.55	Lowest listed price: $12.75	Source09/04/2026
	Modal	Via OpenRoutermodal/mxfp4	$3	$15	Source09/04/2026
	Moonshot AI	Via OpenRoutermoonshotai/mxfp4	$3	$15	Source09/04/2026
	Morph	Via OpenRoutermorph/fast	$6	$22.5	Source09/04/2026
	Morph	Via OpenRoutermorph/fp4	Lowest listed price: $2.5	$14	Source09/04/2026
	Parasail	Via OpenRouterparasail/fp4	$3	$15	Source09/04/2026
	Phala	Via OpenRouterphala	$3	$15	Source09/04/2026
	Sail Research	Via OpenRoutersail-research/fp4	$2.6	$13	Source09/04/2026
	Together	Via OpenRoutertogether	$3	$15	Source09/04/2026
	Wafer	Via OpenRouterwafer	$3	Lowest listed price: $12.75	Source09/04/2026

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-6 Astra

Kimi K3

Coding: 100 / 59.3 (2 benchmark families)

Finance: 99.2 / 96.3 (2 benchmark families)

Legal: 69.6 / 100 (2 benchmark families)

Agentic tasks: 100 / 92.7 (1 benchmark family)

Health: 99.6 / 100 (2 benchmark families)

Education: 85.5 / 100 (1 benchmark family)

Overall: 100 / 86.8 (1 benchmark family)

11 matched rows from 11 benchmark families were considered. The radar shows 7 of 7 comparable categories.

GPT-6 AstraKimi K3

Code MigrationOverall. Higher is better. No documented setup difference

GPT-6 Astra67.74 %

Kimi K316.099 %

EMBOverall. Higher is better. No documented setup difference

GPT-6 Astra71.7 %

Kimi K366.399 %

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

GPT-6 Astra53.54 %

Kimi K354.36 %

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

GPT-6 Astra5.417 %

Kimi K310.833 %

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

GPT-6 Astra39.423 %

Kimi K344.231 %

MedCodeOverall. Higher is better. No documented setup difference

GPT-6 Astra48.486 %

Kimi K348.884 %

MedScribeOverall. Higher is better. No documented setup difference

GPT-6 Astra87.908 %

Kimi K387.958 %

SAGEOverall. Higher is better. No documented setup difference

GPT-6 Astra46.367 %

Kimi K354.26 %

Terminal-Bench 2.1Overall. Higher is better. No documented setup difference

GPT-6 Astra87.266 %

Kimi K380.899 %

Vals IndexOverall. Higher is better. No documented setup difference

GPT-6 Astra66.608 %

Kimi K357.813 %

Vibe Code Bench v1.1Overall. Higher is better. No documented setup difference

GPT-6 Astra89.594 %

Kimi K384.963 %

Key to the marks:better valuebetter, but not conclusivetie

Benchmark scores for GPT-6 Astra and Kimi K3
Benchmark and task	GPT-6 Astra	Kimi K3	Source
Code MigrationOverall Test details No documented difference in the test setupVersion: 1Metric: accuracyScoring: Higher is better	Winner67.74 %	16.099 %	Vals AI Source details Data as of: 09/03/2026
EMBOverall Test details No documented difference in the test setupVersion: 1Metric: accuracyScoring: Higher is better	Winner71.7 %	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	53.54 %	Winner54.36 %	Vals AI Source details Data as of: 09/03/2026
Harvey's Legal Agent BenchmarkOverall · Task fully resolved Test details No documented difference in the test setupVersion: 1Metric: task resolution rateScoring: Higher is better	5.417 %	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	39.423 %	Winner44.231 %	Vals AI Source details Data as of: 09/03/2026
MedCodeOverall Test details No documented difference in the test setupVersion: 1Metric: accuracyScoring: Higher is better	48.486 %	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	87.908 %	Winner87.958 %	Vals AI Source details Data as of: 09/03/2026
SAGEOverall Test details No documented difference in the test setupVersion: 1Metric: accuracyScoring: Higher is better	46.367 %	Winner54.26 %	Vals AI Source details Data as of: 09/03/2026
Terminal-Bench 2.1Overall Test details No documented difference in the test setupVersion: 2.1Metric: accuracyScoring: Higher is better	Winner87.266 %	80.899 %	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	Winner66.608 %	57.813 %	Vals AI Source details Data as of: 09/03/2026
Vibe Code Bench v1.1Overall Test details No documented difference in the test setupVersion: 1.1Metric: accuracyScoring: Higher is betterSettings: Harness: OpenHands	Winner89.594 %	84.963 %	Vals AI Source details Data as of: 09/03/2026
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-6 Astra and Kimi K3 with other leading models using the same data and benchmark logic.

View the complete LLM comparison