All tasks / Comparisons

GPT-6 Astra vs Kimi K3

Compared only on public benchmark results, across the 8 tasks where both are listed: GPT-6 Astra is a tier higher in 4 of 8 shared tasks, Kimi K3 in 1, they share a tier in 2.

GPT-6 Astra

OpenAI's most capable GPT tier, introduced with GPT-6, aimed at complex reasoning and coding.

Vendor: OpenAI
Weights: Closed: API and apps only
Released: 3 Sep 2026
API price: $10 in / $50 out per 1M tokens
License: proprietary
Last verified: 18 Oct 2026

Alternatives to GPT-6 Astra

Kimi K3

Moonshot AI's open-weights Kimi MoE line; Kimi K3 has 2.8T total and 104B activated parameters and 1M context.

Vendor: Moonshot AI
Weights: Open: run it yourself
Released: Jul 2026
API price: $3 in / $15 out per 1M tokens
GPU memory to run locally: ~1600 GB
License: Kimi K3 License
Last verified: 18 Oct 2026

Alternatives to Kimi K3

Task by task

Task	GPT-6 Astra	Kimi K3	Higher tier
Chat & assistants Models	A1,477 on LMArena Text Arena (overall, style control) · Cloud	S1,487 on LMArena Text Arena (overall, style control) · Local	Kimi K3
Writing Models	A1,450 on LMArena Text Arena: Creative Writing (style control) · Cloud	A1,461 on LMArena Text Arena: Creative Writing (style control) · Local	Same tier
Documents & OCR Models	–No public result yet · Cloud	–No public result yet · Local	—
Coding Models	S1,776 on LMArena WebDev / Code Arena (overall) · Cloud	B1,655 on LMArena WebDev / Code Arena (overall) · Local	GPT-6 Astra
Image understanding Models	S1,286 on LMArena Vision Arena (overall, style control) · Cloud	A80.5% on Artificial Analysis MMMU-Pro (independent evaluation) · Local	GPT-6 Astra
Vector graphics & logos Models	B1,431 on Design Arena SVG · Cloud	C1,300 on Design Arena SVG · Local	GPT-6 Astra
Workflow automation Models	A68.5% on AutomationBench-AA (Artificial Analysis) · Cloud	C58.3% on AutomationBench-AA (Artificial Analysis) · Local	GPT-6 Astra
Slides & presentations Models	A1,246 on Design Arena Python-PPTX Slides · Cloud	A1,273 on Design Arena Python-PPTX Slides · Local	Same tier

A tier spans a range of scores, and small gaps on a leaderboard are often within its margin of error, so only a different tier counts as ahead. How we rank.

Same benchmark, both results

Benchmark	GPT-6 Astra	Kimi K3	Snapshot
Artificial Analysis Intelligence Index Composite index over Artificial Analysis' own evaluation suite, higher is better	53 GPT-6 Astra (Max)	44 Kimi K3 (Max)	18 Oct 2026
Artificial Analysis MMMU-Pro (independent evaluation) Accuracy on MMMU-Pro (multi-discipline multimodal questions over images), as run by Artificial Analysis, higher is better	86.9% GPT-6 Astra (Max)	80.5% Kimi K3 (Max)	19 Oct 2026
AutomationBench-AA (Artificial Analysis) Score: average share of each task's objectives completed across 657 business-workflow tasks in 40 simulated SaaS apps via REST APIs; a task with any guardrail (business-rule) violation scores zero, higher is better	68.5% GPT-6 Astra (Max)	58.3% Kimi K3 (Max)	19 Oct 2026
Design Arena Python-PPTX Slides Elo rating from crowdsourced blind pairwise votes on PowerPoint decks that models build with python-pptx in Design Arena's agent harness, higher is better	1,246 GPT-6 Astra (xhigh)	1,273 Kimi K3	18 Oct 2026
Design Arena SVG Elo rating from crowdsourced blind pairwise votes on SVG markup that models generate from a prompt (icons, illustrations, diagrams, artistic compositions), higher is better	1,431 GPT-6 Astra (xhigh)	1,300 Kimi K3	19 Oct 2026
EQ-Bench Creative Writing v3 Elo score from LLM-judged pairwise comparisons of creative-writing outputs (rubric score shown alongside), higher is better	2,173 gpt-6-astra	2,082 kimi-k3	24 Sep 2026
LMArena Text Arena (overall, style control) Arena score (Bradley-Terry rating from pairwise human votes, style-controlled default view), higher is better	1,477 gpt-6-astra-max	1,487 Kimi K3 (Max)	15 Oct 2026
LMArena Text Arena: Creative Writing (style control) Arena score (Bradley-Terry rating from pairwise human votes, creative-writing prompts only, style-controlled view), higher is better	1,450 gpt-6-astra-max	1,461 Kimi K3 (Max)	15 Oct 2026
LMArena WebDev / Code Arena (overall) Arena score (Bradley-Terry rating from pairwise human votes on web-app generation), higher is better	1,776 GPT-6 Astra (Max)	1,655 Kimi K3 (Max)	18 Oct 2026
SWE-Bench Pro V2 (public set, full) Resolve rate on 642 validated long-horizon tasks from 11 copyleft repositories, re-graded on a pristine image under a locked offline protocol, higher is better	96.9% GPT-6-Astra (Codex) high	97.7% Kimi-K3 (mini-swe-agent) max	19 Oct 2026