What is the difference between GPT-6 Astra Pro and Grok 4.20 Beta?

GPT-6 Astra Pro is developed by OpenAI while Grok 4.20 Beta is developed by xAI. GPT-6 Astra Pro has a 1.1M token context window vs Grok 4.20 Beta's 2.0M. 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 Grok 4.20 Beta?

It depends on your use case. GPT-6 Astra Pro and Grok 4.20 Beta 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 Grok 4.20 Beta?

GPT-6 Astra Pro costs $10/M input tokens and Grok 4.20 Beta costs $2/M input tokens. Grok 4.20 Beta is $8.00/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 Grok 4.20 Beta on Rival?

This page shows a side-by-side comparison of GPT-6 Astra Pro and Grok 4.20 Beta 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 ProvsGrok 4.20 Beta

Grok 4.20 Beta is cheaper than GPT-6 Astra Pro at $2/M vs $10/M input tokens.

GPT-6 Astra Pro and Grok 4.20 Beta compared across 6 shared prompts
Spec	GPT-6 Astra Pro	Grok 4.20 Beta
Input price	$10/M tokens	$2/M tokens
Output price	$50/M tokens	$6/M tokens
Context window	1.1M tokens	2.0M tokens
Weights	Closed	Closed
Free API (OpenRouter)	No	No
Released	Sep 2026	Mar 2026

Our Verdict

GPT-6 Astra Pro

Grok 4.20 Beta

Not enough votes to call it. On the specs, nothing separates them.

Grok 4.20 Beta costs 8.3x less per token.

Too close to call

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

Grok 4.20 Beta

Input

$2.00

5.0× cheaper

Output

$6.00

8.3× cheaper

Grok 4.20 Beta is cheaper on both: 5.0× input, 8.3× output.

Where to run it

3 hosts

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

Grok 4.20 Beta1 host

HostInOutContextUptime

xAI$1.25 in$2.50 out2M99.8% up

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

Research

What we learned reading every model

FAQ

Common questions

Keep exploring

More comparisons

Cost per 1M tokens

3 hosts

What we learned reading every model

Common questions

What is the difference between GPT-6 Astra Pro and Grok 4.20 Beta?

Which is better, GPT-6 Astra Pro or Grok 4.20 Beta?

How much does GPT-6 Astra Pro cost compared to Grok 4.20 Beta?

How can I compare GPT-6 Astra Pro and Grok 4.20 Beta on Rival?

More comparisons

Against the newest arrivals

Same lab, same size, long tail

Model pages

Cost per 1M tokens

3 hosts

What we learned reading every model

Common questions

What is the difference between GPT-6 Astra Pro and Grok 4.20 Beta?

Which is better, GPT-6 Astra Pro or Grok 4.20 Beta?

How much does GPT-6 Astra Pro cost compared to Grok 4.20 Beta?

How can I compare GPT-6 Astra Pro and Grok 4.20 Beta on Rival?

More comparisons

Against the newest arrivals

Same lab, same size, long tail

Model pages