What is the difference between Claude Sonnet 5 and DeepSeek V3.1?

Claude Sonnet 5 is developed by Anthropic while DeepSeek V3.1 is developed by DeepSeek. Claude Sonnet 5 has a 1.0M token context window vs DeepSeek V3.1's 164K. You can compare their actual outputs across 53 challenges on Rival to see how they differ in practice.

Which is better, Claude Sonnet 5 or DeepSeek V3.1?

It depends on your use case. Claude Sonnet 5 and DeepSeek V3.1 each have strengths in different areas. Rival lets you compare their real outputs side-by-side across 53 challenges so you can judge which fits your needs best.

How much does Claude Sonnet 5 cost compared to DeepSeek V3.1?

Claude Sonnet 5 costs $2/M input tokens and DeepSeek V3.1 costs $0.2/M input tokens. DeepSeek V3.1 is $1.80/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 Sonnet 5 and DeepSeek V3.1 on Rival?

This page shows a side-by-side comparison of Claude Sonnet 5 and DeepSeek V3.1 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 Jun 2026

Claude Sonnet 5vsDeepSeek V3.1

DeepSeek V3.1 is cheaper than Claude Sonnet 5 at $0.2/M vs $2/M input tokens.

Claude Sonnet 5 and DeepSeek V3.1 compared across 53 shared prompts
Spec	Claude Sonnet 5	DeepSeek V3.1
Input price	$2/M tokens	$0.2/M tokens
Output price	$10/M tokens	$0.8/M tokens
Context window	1.0M tokens	164K tokens
Weights	Closed	Open
Free API (OpenRouter)	No	No
Released	Jun 2026	Aug 2025