OpenAI
GPT 5.1 Thinking
Compact GPT model for low-latency assistance and high-volume workloads
Model facts
- Context window
- 4K tokens
- Maximum output
- 128K tokens
- Cheapest paid input
- $1.25 per 1M tokens
- Cheapest paid output
- $10 per 1M tokens
- Open weights
- no
- Providers
- 2
Capabilities and modalities
reasoning, tool calling, attachments, temperature control, text, image, pdf.
Observed price history
- 2026-08-24: $1.25 input / $10 output per 1M tokens
API providers
- Vercel AI Gateway — model id openai/gpt-5.1-thinking; $1.25 input / $10 output per 1M tokens; provider documentation
- Vercel AI Gateway (Fast) — model id openai/gpt-5.1-thinking-fast; $2.5 input / $20 output per 1M tokens; provider documentation