Question 1

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

Accepted Answer

GPT-5 is developed by OpenAI while Claude Opus 4.1 is developed by Anthropic. GPT-5 has a 400K token context window vs Claude Opus 4.1's 200K. in 104 community votes on RIVAL, Claude Opus 4.1 wins 58% of head-to-head matchups. These results are based on blind head-to-head voting across 27 challenges.

Question 2

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

Accepted Answer

Based on 104 community votes on RIVAL, Claude Opus 4.1 wins 58% of head-to-head matchups against GPT-5. Claude Opus 4.1 is strongest in Web Design, Conversation. However, GPT-5 leads in Image Generation, Reasoning, Analysis.

Question 3

How much does GPT-5 cost compared to Claude Opus 4.1?

Accepted Answer

GPT-5 costs $1.25/M input tokens and Claude Opus 4.1 costs $15/M input tokens. GPT-5 is $13.75/M cheaper per input. The more expensive model wins 58% of duels, so the premium may be justified by quality.

Question 4

How are GPT-5 vs Claude Opus 4.1 votes collected on RIVAL?

Accepted Answer

RIVAL presents both models' outputs side-by-side in blind duels — voters see the responses but don't know which model produced each one. This eliminates brand bias. 104 votes have been collected for this pair across 27 challenges. All vote data is part of RIVAL's open dataset.