Grok 4.5 vs Claude Code: Accepted Changes Per Dollar Is the Real Benchmark

xAI's Grok 4.5 launch (53% on DeepSWE 1.1 vs Opus 4.8's 59%, 29.0% pass@1 on SWE Marathon vs 26.0%, 80 tokens/sec at $2/M input, $6/M output) is worth treating as a practical Claude Code comparison, not just another leaderboard claim. The right metric for developers using AI coding agents is accepted changes per dollar with the same repo, prompt, tool permissions, test command, timeout, and review bar.

Key Details

Grok 4.5 is available in Grok Build, Cursor, and via API. It supports low, medium, and high reasoning modes. However, a third-party test from July 20 (via The New Stack) ran Grok and Opus in Cursor Agent mode on three identical Rust tasks:

• Bug fix: Both passed first-pass tests.
• Multi-file refactor: Both completed, but Opus touched one more file.
• Feature build (the most practical test): Both worked, but Opus added more test coverage and wrote the man-page entry.

Opus's extra touches matter for accepted changes per dollar: a cheaper model that needs one extra repair loop may not be cheaper. The community recommends logging: first-pass test success, rework turns, output tokens, wall-clock time, and reviewer corrections.

Who It's For

Anyone using Claude Code, Cursor, or Grok Build for agentic coding and wanting to evaluate total cost of delivered changes.