What is the difference between Claude Opus 4.1 and GPT-5 Codex?

Claude Opus 4.1 is developed by Anthropic while GPT-5 Codex is developed by OpenAI. in 66 community votes on Rival, Claude Opus 4.1 wins 62% of head-to-head matchups. These results are based on blind head-to-head voting across 49 challenges.

Which is better, Claude Opus 4.1 or GPT-5 Codex?

Based on 66 community votes on Rival, Claude Opus 4.1 wins 62% of head-to-head matchups against GPT-5 Codex. Claude Opus 4.1 is strongest in Web Design, Analysis, Conversation. However, GPT-5 Codex leads in Image Generation, Reasoning.

How are Claude Opus 4.1 vs GPT-5 Codex 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. 66 votes have been collected for this pair across 49 challenges. All vote data is part of Rival's open dataset.

Updated Sep 2025

Claude Opus 4.1vsGPT-5 Codex

Claude Opus 4.1 wins 62% of 66 blind community votes against GPT-5 Codex on Rival.

Claude Opus 4.1 and GPT-5 Codex compared across 49 shared prompts
Spec	Claude Opus 4.1	GPT-5 Codex
Win rate	62%	38%
Input price	$15/M tokens	—
Output price	$75/M tokens	—
Context window	200K tokens	—
Weights	Closed	—
Free API (OpenRouter)	No	No
Released	Aug 2025	Sep 2025
SWE-bench Verified	74.5%	74.5%