OpenAIGPT-5Aug 7, 2025
GPT 5 Nano
GPT-5-Nano is the smallest and fastest variant in the GPT-5 system, optimized for developer tools, rapid interactions, and ultra-low latency environments. While limited in reasoning depth compared to its larger counterparts, it retains key instruction-following and safety features. It is the successor to GPT-4.1-nano and offers a lightweight option for cost-sensitive or real-time applications.
Context Window
400K
tokens
Max Output
128K
tokens
Released
Aug 7, 2025
Arena Rank
—
Capabilities
👁Vision
🧠Reasoning
🔧Tool Calling
⚡Prompt Caching
🖥Computer Use
🎨Image Generation
Supported Parameters
Include Reasoning
Show reasoning tokens
Max Tokens
Output length limit
Reasoning
Extended thinking
Response Format
JSON mode / structured output
Seed
Deterministic outputs
structured_outputs
Tool Choice
Control tool usage
Tool Calling
Function calling support
Pricing Comparison
| Router | Input / 1M | Output / 1M | Cached Input / 1M |
|---|---|---|---|
| Requesty★ | $0.02 | $0.20 | $0.003 |
| OpenRouter | $0.05 | $0.40 | $0.005 |
| Vercel AI | $0.05 | $0.40 | — |
| Martian | $0.05 | $0.40 | $0.005 |
Model IDs
Requesty
openai/gpt-5-nano:flexOpenRouter
openai/gpt-5-nanoTags
visionreasoningtool-callingcaching
Available Regions
EUUS