Last updated: April 5, 2026 · Reviewed by Daniel Ashford
🔥GPT-5.3 Codex vs Claude Sonnet 4
Head-to-head across 6 dimensions · by Daniel Ashford
Summary
GPT-5.3 Codex leads overall with an Index of 95.2 vs 93.2. GPT-5.3 Codex wins on accuracy, reasoning, coding, creativity, instruction. Claude Sonnet 4 wins on safety. On pricing, Claude Sonnet 4 is more affordable.
❓ Frequently Asked Questions
Is GPT-5.3 Codex better than Claude Sonnet 4?
Based on the LLM Judge Index™, GPT-5.3 Codex scores higher overall (95.2 vs 93.2). GPT-5.3 Codex leads on accuracy, reasoning, coding, creativity, instruction, while Claude Sonnet 4 leads on safety.
Which is cheaper, GPT-5.3 Codex or Claude Sonnet 4?
Claude Sonnet 4 is more affordable at $3/M tokens.
Which is better for coding?
GPT-5.3 Codex scores higher on coding (97 vs 91).
Which model is safer?
Claude Sonnet 4 has a higher safety score (96 vs 93).