GPT-5.3 Instant
GPT-5.3 Instant is the conversational GPT-5.3 model used in ChatGPT and exposed through the gpt-5.3-chat-latest alias. It prioritizes responsive everyday conversation and image understanding rather than long reasoning runs. The alias can change snapshots and is not a fixed checkpoint. This record preserves the distinct released Instant model despite subsequent deprecation.
2026-03-03
Unreleased
Undisclosed proprietary architecture
Proprietary
Specifications
- Parameters
- Unreleased
- Architecture
- Undisclosed proprietary architecture
- License
- Proprietary
- Context Window
- 128,000 tokens
- Max Output
- 16,384 tokens
- Training Data Cutoff
- Aug 31, 2025
- Type
- multimodal
- Modalities
- textimage
Benchmark Scores
Advanced Specifications
- Model Family
- GPT-5
- API Access
- Available
- Chat Interface
- Not Available
- Variants
- gpt-5.3-chat-latest
Capabilities & Limitations
- Capabilities
- conversationvisionwritingcode
- Known Limitations
- Can produce incorrect factual claims or code; important results require independent verification.
- Notable Use Cases
- everyday assistancewriting supportinteractive question answering
- Function Calling Support
- Yes
- Tool Use Support
- Yes