Plain-English Summary
OpenAI's previous flagship for complex professional work, with configurable reasoning effort.
GPT-5.2
OpenAI's previous flagship for complex professional work, with configurable reasoning effort.
Maker
OpenAI
GPT-5
Reasoning LLM
Legacy
Open weights: No
API: Yes
Technical Notes
Reasoning model with 400K context, 128K max output, text and image input, and configurable reasoning effort.
Best For
Professional knowledge work, analysis and agentic tasks
Watch Out For
Superseded by newer OpenAI flagships; knowledge cutoff Aug 2025.
Model Specs
- Maker
- OpenAI
- Country
- USA
- Family
- GPT-5
- Type
- Reasoning LLM
- Release date
- 2025-12-11
- Date confidence
- Model ID date
- Status
- Legacy
- Context window
- 400,000 tokens
- Max output
- 128,000
- Parameters
- Not disclosed
- Active parameters
- Not disclosed
- Architecture
- Not listed
- Reasoning
- Yes — configurable effort
- Tool calling
- Yes
- Structured output
- Yes
- API available
- Yes
- Open weights
- No
- Self-hostable
- No
- License
- Proprietary
- Inputs
- Text, image
- Outputs
- Text
- Approx. price
- $1.75 input / $14 output per 1M tokens
- How to access
- OpenAI API
- Model / API ID
- gpt-5.2-2025-12-11
- Knowledge cutoff
- 2025-08-31
- Fine-tuning
- Not listed
- Completeness
- Not listed
- Verified
- Snapshot date
- Source
- Official source