GPT-5.3-Codex-Spark
Ultra-fast variant of GPT-5.3-Codex optimized for rapid iteration and quick coding tasks
GPT-5.3-Codex-Spark
OpenAI • February 2026
Training Data
Up to December 2025
GPT-5.3-Codex-Spark
February 2026
Parameters
~200 billion
Training Method
Speed-optimized Code Training
Context Window
400,000 tokens
Knowledge Cutoff
December 2025
Key Features
Ultra Fast Coding • Rapid Iteration • Quick Tasks • Low Latency
Capabilities
Speed: Maximum
Coding: Excellent
Iteration: Outstanding
What's New in This Version
Ultra-fast coding variant for rapid prototyping and quick development tasks
Ultra-fast variant of GPT-5.3-Codex optimized for rapid iteration and quick coding tasks
What's New in This Version
Ultra-fast coding variant for rapid prototyping and quick development tasks
Technical Specifications
Key Features
Capabilities
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