Claude Sonnet 4.5vsGrok 4.3 Beta

Claude Sonnet 4.5
Grok 4.3 Beta
Benchmarks
Nonsense detection
BullshitBench v2
79%Best
50%
Coding
SWE-Bench Verified
77.2%
Next.js coding
Next.js Evals
50%
Science
GPQA Diamond
83.4%
Multimodal
MMMU
68%
Overview
CompanyAnthropicSpaceXAI
Release dateSep 29 2025Apr 17 2026
AccessProprietaryProprietary

Which is better: Claude Sonnet 4.5 or Grok 4.3 Beta?

Claude Sonnet 4.5 leads Grok 4.3 Beta on 1 of the 1 benchmark they both report (BullshitBench v2). Claude Sonnet 4.5 shipped 200 days before Grok 4.3 Beta, 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 BullshitBench v2, Claude Sonnet 4.5 leads at 79% vs Grok 4.3 Beta at 50%.

Frequently asked questions

Claude Sonnet 4.5 was released by Anthropic on Sep 29 2025.

Grok 4.3 Beta was released by SpaceXAI on Apr 17 2026.

Other comparisons