Claude Sonnet 5vsDeepSeek-V4-Flash-0731

Claude Sonnet 5
DeepSeek-V4-Flash-0731
Benchmarks
Nonsense detection
BullshitBench v2
80%
Prompt injection robustness
Gray Swan IPI · k = 1
0.6%
Prompt injection robustness
Gray Swan IPI · k = 10
4.7%
Prompt injection robustness
Gray Swan IPI · k = 15
5.9%
Agentic coding
SWE-Bench Pro
63.2%
Agentic coding
CursorBench v3.2
61.5%
Agentic coding
CursorBench v3.1
61.2%
Agentic computer work
Frontier-Bench v0.1
14.6%
Agentic terminal coding
Terminal-Bench 2.1
80.4%
82.7%Best
Personal tool use
Toolathlon-Verified
70.3%
Web browsing
BrowseComp
84.7%
Cybersecurity
CyberGym
76.7%
Multidisciplinary reasoning
Humanity's Last Exam · no tools
43.2%
Multidisciplinary reasoning
Humanity's Last Exam · with tools
57.4%
Agentic computer use
OSWorld-Verified
81.2%
Business workflows
AutomationBench
25.1%
Knowledge work
GDPval-AA
1618
Community preference (code)
Arena Elo (Code)
1543
Overview
CompanyAnthropicDeepSeek
Release dateJun 30 2026Jul 31 2026
AccessProprietaryProprietary

Which is better: Claude Sonnet 5 or DeepSeek-V4-Flash-0731?

DeepSeek-V4-Flash-0731 leads Claude Sonnet 5 on 1 of the 1 benchmark they both report (Terminal-Bench 2.1). Claude Sonnet 5 shipped 31 days before DeepSeek-V4-Flash-0731, so benchmark comparisons should account for the intervening progress.

Published specifications for these two models are limited — see each model page for the latest details.

On Terminal-Bench 2.1, DeepSeek-V4-Flash-0731 leads at 82.7% vs Claude Sonnet 5 at 80.4%.

Frequently asked questions

Claude Sonnet 5 was released by Anthropic on Jun 30 2026.

DeepSeek-V4-Flash-0731 was released by DeepSeek on Jul 31 2026.

DeepSeek-V4-Flash-0731 leads on Terminal-Bench 2.1 — Claude Sonnet 5 80.4% vs DeepSeek-V4-Flash-0731 82.7%.

Other comparisons