What is the difference between GPT-5 Codex and Grok 4.5?

GPT-5 Codex is developed by OpenAI while Grok 4.5 is developed by xAI. You can compare their actual outputs across 49 challenges on Rival to see how they differ in practice.

Which is better, GPT-5 Codex or Grok 4.5?

It depends on your use case. GPT-5 Codex and Grok 4.5 each have strengths in different areas. Rival lets you compare their real outputs side-by-side across 49 challenges so you can judge which fits your needs best.

How can I compare GPT-5 Codex and Grok 4.5 on Rival?

This page shows a side-by-side comparison of GPT-5 Codex and Grok 4.5 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.

What is the difference between GPT-5 Codex and Grok 4.5?

GPT-5 Codex is developed by OpenAI while Grok 4.5 is developed by xAI. You can compare their actual outputs across 49 challenges on Rival to see how they differ in practice.

Which is better, GPT-5 Codex or Grok 4.5?

It depends on your use case. GPT-5 Codex and Grok 4.5 each have strengths in different areas. Rival lets you compare their real outputs side-by-side across 49 challenges so you can judge which fits your needs best.

How can I compare GPT-5 Codex and Grok 4.5 on Rival?

This page shows a side-by-side comparison of GPT-5 Codex and Grok 4.5 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.

GPT-5 Codex vs Grok 4.5: Which Is Better?

Updated Jul 2026

Our Verdict

GPT-5 Codex

Grok 4.5

No community votes yet. On paper, these are closely matched - try both with your actual task to see which fits your workflow.

Too close to call

What do GPT-5 Codex and Grok 4.5 say about your brand?

10 models, one question, verbatim receipts.

or peek at a demo: Notion Linear Vercel

API pricing

Cost per 1M tokens

GPT-5 Codex

Input

—

Output

—

Grok 4.5

Input

$2.00

Output

$6.00

Writing DNA

Style Comparison

Similarity

57%

GPT-5 Codex uses 1.7x more hedging

GPT-5 Codex

Grok 4.5

64%Vocabulary61%

17wSentence Length16w

0.38Hedging0.23

2.3Bold2.5

3.5Lists2.4

0.15Emoji0.09

0.49Headings0.48

0.05Transitions0.06

Based on 13 + 27 text responses

Research

What we learned reading every model

FAQ

Common questions

Keep exploring

More comparisons

GPT-5 Codex vs MiniMax M3New provider

GPT-5 Codex vs Ox AlphaNew provider

GPT-5 Codex vs Llama 4 MaverickNew provider

Updated Jul 2026

Our Verdict

GPT-5 Codex

Grok 4.5

No community votes yet. On paper, these are closely matched - try both with your actual task to see which fits your workflow.

Too close to call

What do GPT-5 Codex and Grok 4.5 say about your brand?

10 models, one question, verbatim receipts.

or peek at a demo: Notion Linear Vercel

API pricing

Cost per 1M tokens

GPT-5 Codex

Input

—

Output

—

Grok 4.5

Input

$2.00

Output

$6.00

Writing DNA

Style Comparison

Similarity

57%

GPT-5 Codex uses 1.7x more hedging

GPT-5 Codex

Grok 4.5

64%Vocabulary61%

17wSentence Length16w

0.38Hedging0.23

2.3Bold2.5

3.5Lists2.4

0.15Emoji0.09

0.49Headings0.48

0.05Transitions0.06

Based on 13 + 27 text responses

Research

What we learned reading every model

FAQ

Common questions

Keep exploring

More comparisons

GPT-5 Codex vs MiniMax M3New provider

GPT-5 Codex vs Ox AlphaNew provider

GPT-5 Codex vs Llama 4 MaverickNew provider