Claude Opus 4.6 vs GPT-5.3 Codex: Specs & Benchmark Comparison
| Characteristic | Claude Opus 4.6 | GPT-5.3 Codex |
|---|---|---|
| Company | Anthropic | OpenAI |
| Release Date | February 4, 2026 | February 5, 2026 |
| Parameters | — | — |
| Multimodal | Yes | Yes |
| Context (input) | 1.0M | 400K |
| Context (output) | 128K | 128K |
| Input Price / 1M | $5.00 | $1.75 |
| Output Price / 1M | $25.00 | $14.00 |
| Average Score | 0.8 | 0.7 |
Verdict
Both models show equal results — the choice depends on your specific use case.
Overall Performance
Both models show comparable average scores: Claude Opus 4.6 — 0.8, GPT-5.3 Codex — 0.7.
API Cost
GPT-5.3 Codex is 1.9x cheaper: input $1.75/1M vs $5.00/1M tokens.
Context Window
Claude Opus 4.6 supports a larger context: 1M vs 400K tokens.
Recency
Both models were released around the same time: 2/4/2026 and 2/5/2026.
More About These Models
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The Claude Opus 4.6 and GPT-5.3 Codex comparison is updated for 2026. Data includes benchmark results, API pricing, context window size and other specifications. For more detailed information, visit the Claude Opus 4.6 or GPT-5.3 Codex page. See also the complete list of AI model comparisons.