Last updated: April 5, 2026 · Reviewed by Daniel Ashford

👑Claude Opus 4 vs 🔥GPT-5.3 Codex

Head-to-head across 6 dimensions · by Daniel Ashford

DIMENSION
👑 Claude Opus 4
Anthropic
🔥 GPT-5.3 Codex
OpenAI
🎯 Accuracy97 👑96
🧠 Reasoning96 👑95
🛡️ Safety98 👑93
💻 Coding9497 👑
Creativity96 👑94
📋 Instruction9596 👑
Overall Index™96.0 👑95.2
Try on Anthropic →Try on OpenAI →

Summary

Claude Opus 4 leads overall with an Index of 96.0 vs 95.2. Claude Opus 4 wins on accuracy, reasoning, safety, creativity. GPT-5.3 Codex wins on coding, instruction. On pricing, GPT-5.3 Codex is more affordable.

❓ Frequently Asked Questions

Is Claude Opus 4 better than GPT-5.3 Codex?

Based on the LLM Judge Index™, Claude Opus 4 scores higher overall (96.0 vs 95.2). Claude Opus 4 leads on accuracy, reasoning, safety, creativity, while GPT-5.3 Codex leads on coding, instruction.

Which is cheaper, Claude Opus 4 or GPT-5.3 Codex?

GPT-5.3 Codex is more affordable at $10/M tokens.

Which is better for coding?

GPT-5.3 Codex scores higher on coding (97 vs 94).

Which model is safer?

Claude Opus 4 has a higher safety score (98 vs 93).

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