Introducing GPT-5.3-Codex-Spark
What changed
Introducing GPT-5.3-Codex-Spark—our first real-time coding model. 15x faster generation, 128k context, now in research preview for ChatGPT Pro users.
Why it matters
A concrete addition to Practical AI: Tools, Models & Frameworks: it changes what's available to builders today rather than being general commentary.
How it compares
Related prior coverage to compare against:
- Introducing Codex
- Introducing GPT-5.3-Codex
- Building more with GPT-5.1-Codex-Max
Sources
- Introducing GPT-5.3-Codex-Spark (openai-blog)primary