What is the difference between GPT-6 Astra Pro and Kimi K2.5?

GPT-6 Astra Pro is developed by OpenAI while Kimi K2.5 is developed by Moonshot AI. GPT-6 Astra Pro has a 1.1M token context window vs Kimi K2.5's 262K. You can compare their actual outputs across 6 challenges on Rival to see how they differ in practice.

Which is better, GPT-6 Astra Pro or Kimi K2.5?

It depends on your use case. GPT-6 Astra Pro and Kimi K2.5 each have strengths in different areas. Rival lets you compare their real outputs side-by-side across 6 challenges so you can judge which fits your needs best.

How much does GPT-6 Astra Pro cost compared to Kimi K2.5?

GPT-6 Astra Pro costs $10/M input tokens and Kimi K2.5 costs $0.6/M input tokens. Kimi K2.5 is $9.40/M cheaper per input. Check their side-by-side outputs on Rival to see if the price difference is justified by quality.

How can I compare GPT-6 Astra Pro and Kimi K2.5 on Rival?

This page shows a side-by-side comparison of GPT-6 Astra Pro and Kimi K2.5 across shared challenges. You can vote on which model produced the better output in a blind duel. Browsing and voting are free. No account is needed to look; signing in only saves your votes and likes.

Updated Sep 2026

GPT-6 Astra ProvsKimi K2.5

Kimi K2.5 is cheaper than GPT-6 Astra Pro at $0.6/M vs $10/M input tokens.

GPT-6 Astra Pro and Kimi K2.5 compared across 6 shared prompts
Spec	GPT-6 Astra Pro	Kimi K2.5
Input price	$10/M tokens	$0.6/M tokens
Output price	$50/M tokens	$3/M tokens
Context window	1.1M tokens	262K tokens
Weights	Closed	Open
Free API (OpenRouter)	No	No
Released	Sep 2026	Jan 2026

Our Verdict

GPT-6 Astra Pro

Kimi K2.5Runner-up

Not enough votes to call it. On the specs, GPT-6 Astra Pro has the edge: bigger model tier, newer, bigger context window, major provider backing.

Kimi K2.5 costs 17x less per token.

Slight edge

Reviewing agent-written code?See a Brief PR report

API pricing

Cost per 1M tokens

GPT-6 Astra Pro

Input

$10.00

Output

$50.00

Kimi K2.5

Input

$0.60

17× cheaper

Output

$3.00

17× cheaper

Kimi K2.5 is cheaper on both: 17× input, 17× output.

Where to run it

8 hosts, cheapest first

GPT-6 Astra Pro2 hosts

HostInOutContextUptime

Azure AI Foundry$10.00 in$50.00 out1.1M99.8% up OpenAI$10.00 in$50.00 out1.1M99.8% up

Kimi K2.56 hosts

HostInOutContextUptime

SiliconFlowint4$0.45 in$2.25 out262k99.8% up AtlasCloudint4$0.49 in$2.50 out262k99.6% up Venice$0.53 in$3.33 out256k99.9% up Amazon Bedrock$0.60 in$3.00 out262k94.7% up Phala$0.60 in$3.00 out262k98.6% up Novitadegraded$0.57 in$2.85 out262k95.3% up

Per million tokens. Prices and uptime via OpenRouter, checked 16 Sep 2026.

Research

What we learned reading every model

FAQ

Common questions

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More comparisons

Cost per 1M tokens

8 hosts, cheapest first

What we learned reading every model

Common questions

What is the difference between GPT-6 Astra Pro and Kimi K2.5?

Which is better, GPT-6 Astra Pro or Kimi K2.5?

How much does GPT-6 Astra Pro cost compared to Kimi K2.5?

How can I compare GPT-6 Astra Pro and Kimi K2.5 on Rival?

More comparisons

Against the newest arrivals

Same lab, same size, long tail

Model pages

Cost per 1M tokens

8 hosts, cheapest first

What we learned reading every model

Common questions

What is the difference between GPT-6 Astra Pro and Kimi K2.5?

Which is better, GPT-6 Astra Pro or Kimi K2.5?

How much does GPT-6 Astra Pro cost compared to Kimi K2.5?

How can I compare GPT-6 Astra Pro and Kimi K2.5 on Rival?

More comparisons

Against the newest arrivals

Same lab, same size, long tail

Model pages