What is the difference between GPT-5.3-Codex and Grok 3?

GPT-5.3-Codex is developed by OpenAI while Grok 3 is developed by xAI. GPT-5.3-Codex has a 400K token context window vs Grok 3's 128K. in 2 community votes on Rival, GPT-5.3-Codex wins 100% of head-to-head matchups. These results are based on blind head-to-head voting across 52 challenges.

Which is better, GPT-5.3-Codex or Grok 3?

Based on 2 community votes on Rival, GPT-5.3-Codex wins 100% of head-to-head matchups against Grok 3.

How are GPT-5.3-Codex vs Grok 3 votes collected on Rival?

Rival presents both models' outputs side-by-side in blind duels. Voters see the responses but don't know which model produced each one, eliminating brand bias. 2 votes have been collected for this pair across 52 challenges. All vote data is part of Rival's open dataset.

What is the difference between GPT-5.3-Codex and Grok 3?

GPT-5.3-Codex is developed by OpenAI while Grok 3 is developed by xAI. GPT-5.3-Codex has a 400K token context window vs Grok 3's 128K. in 2 community votes on Rival, GPT-5.3-Codex wins 100% of head-to-head matchups. These results are based on blind head-to-head voting across 52 challenges.

Which is better, GPT-5.3-Codex or Grok 3?

Based on 2 community votes on Rival, GPT-5.3-Codex wins 100% of head-to-head matchups against Grok 3.

How are GPT-5.3-Codex vs Grok 3 votes collected on Rival?

Rival presents both models' outputs side-by-side in blind duels. Voters see the responses but don't know which model produced each one, eliminating brand bias. 2 votes have been collected for this pair across 52 challenges. All vote data is part of Rival's open dataset.

GPT-5.3-Codex vs Grok 3: Which Is Better?

Updated Feb 2026

Our Verdict

GPT-5.3-CodexWinner

Grok 3Runner-up

Pick GPT-5.3-Codex. In 2 blind votes, GPT-5.3-Codex wins 100% of the time. That's not luck.

Clear winner

API pricing

Cost per 1M tokens

GPT-5.3-Codex

Input

$1.75

Output

$14.00

Grok 3

Input

—

Output

—

Writing DNA

Style Comparison

Similarity

42%

GPT-5.3-Codex uses 4.0x more emoji

GPT-5.3-Codex

Grok 3

65%Vocabulary49%

23wSentence Length18w

0.51Hedging0.94

6.5Bold2.5

6.2Lists3.0

0.16Emoji0.04

1.90Headings0.65

0.03Transitions0.08

Based on 23 + 17 text responses

Research

What we learned reading every model

GPT-5.3-Codex and Grok 3 have opinions about your brand too.Ask 10 models what they tell people about you. Verbatim receipts.Run the mirror

FAQ

Common questions

Keep exploring

More comparisons

Grok 3 vs MiniMax M3New provider

Grok 3 vs Claude Opus 4New provider

Grok 3 vs Gemini 2.5 Pro Preview 06-05New provider

Updated Feb 2026

Our Verdict

GPT-5.3-CodexWinner

Grok 3Runner-up

Pick GPT-5.3-Codex. In 2 blind votes, GPT-5.3-Codex wins 100% of the time. That's not luck.

Clear winner

API pricing

Cost per 1M tokens

GPT-5.3-Codex

Input

$1.75

Output

$14.00

Grok 3

Input

—

Output

—

Writing DNA

Style Comparison

Similarity

42%

GPT-5.3-Codex uses 4.0x more emoji

GPT-5.3-Codex

Grok 3

65%Vocabulary49%

23wSentence Length18w

0.51Hedging0.94

6.5Bold2.5

6.2Lists3.0

0.16Emoji0.04

1.90Headings0.65

0.03Transitions0.08

Based on 23 + 17 text responses

Research

What we learned reading every model

GPT-5.3-Codex and Grok 3 have opinions about your brand too.Ask 10 models what they tell people about you. Verbatim receipts.Run the mirror

FAQ

Common questions

Keep exploring

More comparisons

Grok 3 vs MiniMax M3New provider

Grok 3 vs Claude Opus 4New provider

Grok 3 vs Gemini 2.5 Pro Preview 06-05New provider