GPT-5.3 Codex vs Kimi K2.5: Specs & Benchmark Comparison

CharacteristicGPT-5.3 CodexKimi K2.5
CompanyOpenAIMoonshot AI
Release DateFebruary 5, 2026January 26, 2026
Parameters1.0T
MultimodalYesYes
Context (input)400K
Context (output)128K
Input Price / 1M$1.75
Output Price / 1M$14.00
Average Score0.70.9

Verdict

Both models show equal results — the choice depends on your specific use case.

Overall Performance

Both models show comparable average scores: GPT-5.3 Codex — 0.7, Kimi K2.5 — 0.9.

Recency

Both models were released around the same time: 2/5/2026 and 1/26/2026.

More About These Models

Related Comparisons

The GPT-5.3 Codex and Kimi K2.5 comparison is updated for 2026. Data includes benchmark results, API pricing, context window size and other specifications. For more detailed information, visit the GPT-5.3 Codex or Kimi K2.5 page. See also the complete list of AI model comparisons.