Claude Sonnet 4.6 vs GPT-5.3 Codex: Specs & Benchmark Comparison

CharacteristicClaude Sonnet 4.6GPT-5.3 Codex
CompanyAnthropicOpenAI
Release DateFebruary 17, 2026February 5, 2026
Parameters
MultimodalYesYes
Context (input)200K400K
Context (output)64K128K
Input Price / 1M$3.00$1.75
Output Price / 1M$15.00$14.00
Average Score0.70.7

Verdict

GPT-5.3 Codex leads in 2 out of 4 comparison categories.

Overall Performance

Both models show comparable average scores: Claude Sonnet 4.6 — 0.7, GPT-5.3 Codex — 0.7.

API Cost

GPT-5.3 Codex is 1.1x cheaper: input $1.75/1M vs $3.00/1M tokens.

Context Window

GPT-5.3 Codex supports a larger context: 400K vs 200K tokens.

Recency

Both models were released around the same time: 2/17/2026 and 2/5/2026.

More About These Models

Related Comparisons

The Claude Sonnet 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 Sonnet 4.6 or GPT-5.3 Codex page. See also the complete list of AI model comparisons.