Overview
- GPT‑5.4 mini is live in ChatGPT for Free and Go users via the Thinking option and in the API and Codex, while GPT‑5.4 nano launches API‑only for developer use.
- OpenAI lists GPT‑5.4 mini at $0.75 per million input tokens and $4.50 per million output tokens with a 400k context window; GPT‑5.4 nano costs $0.20 and $1.25 respectively.
- Benchmarks reported by OpenAI show mini nearing the flagship on coding and computer‑use tests (e.g., 54.38% on SWE‑Bench Pro and 72.13% on OSWorld‑Verified) while running more than 2x faster than GPT‑5 mini.
- Mini serves as a cost‑saving executor in Codex, using about 30% of a standard GPT‑5.4 quota, as OpenAI promotes hybrid architectures where a planning model delegates to cheaper subagents.
- Early tests from customers and third parties, including Hebbia, Notion, and Perplexity, cite strong task performance for mini and responsiveness and efficiency gains for nano in live workflows.