What is the difference between Claude Opus 4.8 and GPT-5?

Claude Opus 4.8 is developed by Anthropic while GPT-5 is developed by OpenAI. Claude Opus 4.8 has a 1.0M token context window vs GPT-5's 400K. You can compare their actual outputs across 51 challenges on Rival to see how they differ in practice.

Which is better, Claude Opus 4.8 or GPT-5?

It depends on your use case. Claude Opus 4.8 and GPT-5 each have strengths in different areas. Rival lets you compare their real outputs side-by-side across 51 challenges so you can judge which fits your needs best.

How much does Claude Opus 4.8 cost compared to GPT-5?

Claude Opus 4.8 costs $5/M input tokens and GPT-5 costs $1.25/M input tokens. GPT-5 is $3.75/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 Opus 4.8 and GPT-5 on Rival?

This page shows a side-by-side comparison of Claude Opus 4.8 and GPT-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.

Updated May 2026

Claude Opus 4.8vsGPT-5

GPT-5 is cheaper than Claude Opus 4.8 at $1.25/M vs $5/M input tokens.

Claude Opus 4.8 and GPT-5 compared across 51 shared prompts
Spec	Claude Opus 4.8	GPT-5
Input price	$5/M tokens	$1.25/M tokens
Output price	$25/M tokens	$10/M tokens
Context window	1.0M tokens	400K tokens
Weights	Closed	Closed
Free API (OpenRouter)	No	No
Released	May 2026	Aug 2025