OpenAI
GPT-5.3 Chat (latest)
Chat-tuned GPT model for conversational assistance, writing, and tool workflows
Model facts
- Context window
- 4K tokens
- Maximum output
- 128K tokens
- Cheapest paid input
- $1.75 per 1M tokens
- Cheapest paid output
- $14 per 1M tokens
- Open weights
- no
- Providers
- 2
Capabilities and modalities
reasoning, tool calling, structured output, attachments, temperature control, text, image, pdf.
Observed price history
- 2026-08-24: $1.75 input / $14 output per 1M tokens
API providers
- Abacus — model id gpt-5.3-chat-latest; $1.75 input / $14 output per 1M tokens; provider documentation
- Merge Gateway — model id openai/gpt-5.3-chat-latest; $1.75 input / $14 output per 1M tokens; provider documentation