What is the difference between Claude Sonnet 4.6 and GPT-5.1-Codex?

Claude Sonnet 4.6 is developed by Anthropic while GPT-5.1-Codex is developed by OpenAI. Claude Sonnet 4.6 has a 1.0M token context window vs GPT-5.1-Codex's 400K. You can compare their actual outputs across 52 challenges on Rival to see how they differ in practice.

Which is better, Claude Sonnet 4.6 or GPT-5.1-Codex?

It depends on your use case. Claude Sonnet 4.6 and GPT-5.1-Codex each have strengths in different areas. Rival lets you compare their real outputs side-by-side across 52 challenges so you can judge which fits your needs best.

How much does Claude Sonnet 4.6 cost compared to GPT-5.1-Codex?

Claude Sonnet 4.6 costs $3/M input tokens and GPT-5.1-Codex costs $1.25/M input tokens. GPT-5.1-Codex is $1.75/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 Claude Sonnet 4.6 and GPT-5.1-Codex on Rival?

This page shows a side-by-side comparison of Claude Sonnet 4.6 and GPT-5.1-Codex 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.

What is the difference between Claude Sonnet 4.6 and GPT-5.1-Codex?

Claude Sonnet 4.6 is developed by Anthropic while GPT-5.1-Codex is developed by OpenAI. Claude Sonnet 4.6 has a 1.0M token context window vs GPT-5.1-Codex's 400K. You can compare their actual outputs across 52 challenges on Rival to see how they differ in practice.

Which is better, Claude Sonnet 4.6 or GPT-5.1-Codex?

It depends on your use case. Claude Sonnet 4.6 and GPT-5.1-Codex each have strengths in different areas. Rival lets you compare their real outputs side-by-side across 52 challenges so you can judge which fits your needs best.

How much does Claude Sonnet 4.6 cost compared to GPT-5.1-Codex?

Claude Sonnet 4.6 costs $3/M input tokens and GPT-5.1-Codex costs $1.25/M input tokens. GPT-5.1-Codex is $1.75/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 Claude Sonnet 4.6 and GPT-5.1-Codex on Rival?

This page shows a side-by-side comparison of Claude Sonnet 4.6 and GPT-5.1-Codex 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 Feb 2026

Claude Sonnet 4.6vsGPT-5.1-Codex

GPT-5.1-Codex is cheaper than Claude Sonnet 4.6 at $1.25/M vs $3/M input tokens.

Claude Sonnet 4.6 and GPT-5.1-Codex compared across 52 shared prompts
Spec	Claude Sonnet 4.6	GPT-5.1-Codex
Input price	$3/M tokens	$1.25/M tokens
Output price	$15/M tokens	$10/M tokens
Context window	1.0M tokens	400K tokens
Released	Feb 2026	Nov 2025
SWE-bench Verified	79.0%	73.7%

Our Verdict

Claude Sonnet 4.6

GPT-5.1-Codex

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

Too close to call

What do Claude Sonnet 4.6 and GPT-5.1-Codex say about your brand?

10 models, one question, verbatim receipts.

or peek at a demo: Notion Linear Vercel

API pricing

Cost per 1M tokens

Claude Sonnet 4.6

Input

$3.00

Output

$15.00

GPT-5.1-Codex

Input

$1.25

2.4× cheaper

Output

$10.00

1.5× cheaper

GPT-5.1-Codex is cheaper on both — 2.4× input, 1.5× output

Writing DNA

Style Comparison

Similarity

34%

Claude Sonnet 4.6 uses 19.1x more emoji

Claude Sonnet 4.6

GPT-5.1-Codex

56%Vocabulary70%

36wSentence Length17w

0.53Hedging0.39

5.1Bold3.4

3.4Lists3.5

0.19Emoji0.00

2.10Headings0.50

0.02Transitions0.38

Based on 23 + 14 text responses

Research

What we learned reading every model

FAQ

Common questions

Keep exploring

More comparisons

GPT-5.1-Codex vs MiniMax M3New provider

GPT-5.1-Codex vs Ox AlphaNew provider

GPT-5.1-Codex vs Gemini 2.5 Pro Preview 06-05New provider

GPT-5.1-Codex vs MiniMax M1New provider

GPT-5.1-Codex vs Ling 2.6 1TNew provider

Claude Sonnet 4.6 vs Ling 2.6 FlashNew provider

Claude Sonnet 4.6 vs Llama 3 70BNew provider

Claude Sonnet 4.6 vs Llama 3.1 405BNew provider

Updated Feb 2026

Claude Sonnet 4.6vsGPT-5.1-Codex

GPT-5.1-Codex is cheaper than Claude Sonnet 4.6 at $1.25/M vs $3/M input tokens.

Claude Sonnet 4.6 and GPT-5.1-Codex compared across 52 shared prompts
Spec	Claude Sonnet 4.6	GPT-5.1-Codex
Input price	$3/M tokens	$1.25/M tokens
Output price	$15/M tokens	$10/M tokens
Context window	1.0M tokens	400K tokens
Released	Feb 2026	Nov 2025
SWE-bench Verified	79.0%	73.7%

Our Verdict

Claude Sonnet 4.6

GPT-5.1-Codex

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

Too close to call

What do Claude Sonnet 4.6 and GPT-5.1-Codex say about your brand?

10 models, one question, verbatim receipts.

or peek at a demo: Notion Linear Vercel

API pricing

Cost per 1M tokens

Claude Sonnet 4.6

Input

$3.00

Output

$15.00

GPT-5.1-Codex

Input

$1.25

2.4× cheaper

Output

$10.00

1.5× cheaper

GPT-5.1-Codex is cheaper on both — 2.4× input, 1.5× output

Writing DNA

Style Comparison

Similarity

34%

Claude Sonnet 4.6 uses 19.1x more emoji

Claude Sonnet 4.6

GPT-5.1-Codex

56%Vocabulary70%

36wSentence Length17w

0.53Hedging0.39

5.1Bold3.4

3.4Lists3.5

0.19Emoji0.00

2.10Headings0.50

0.02Transitions0.38

Based on 23 + 14 text responses

Research

What we learned reading every model

FAQ

Common questions

Keep exploring

More comparisons

GPT-5.1-Codex vs MiniMax M3New provider

GPT-5.1-Codex vs Ox AlphaNew provider

GPT-5.1-Codex vs Gemini 2.5 Pro Preview 06-05New provider

GPT-5.1-Codex vs MiniMax M1New provider

GPT-5.1-Codex vs Ling 2.6 1TNew provider

Claude Sonnet 4.6 vs Ling 2.6 FlashNew provider

Claude Sonnet 4.6 vs Llama 3 70BNew provider

Claude Sonnet 4.6 vs Llama 3.1 405BNew provider