GPT-5.4 brings together advances in reasoning, coding, and agentic workflows in a single frontier model. It set a new state of the art on GDPval, matching or exceeding industry professionals in 83% of comparisons across 44 occupations, making it strong for demanding knowledge work. With a 1M token context window, GPT-5.4 handles multimodal input across text and vision, function calling, structured output, and reasoning. It is highly token-efficient for a reasoning model, delivering polished results on real-world professional tasks while keeping output concise. GPT-5.4 supports configurable reasoning effort levels and interleaved thinking, so the model can generate visible output and reason between tool calls. It excels at debugging code, analyzing complex data, research, and agentic workflows that require sustained reasoning across many steps.
GPT-5.4 runs on 2 different routes through the Opper gateway. Compare residency, ZDR, and training posture at a glance β full data-handling detail per route below.
Training posture across routes: No training on prompts by default.
Each route hosting GPT-5.4 has its own privacy posture, residency, and GDPR terms. Postures are maintained by Opper with a last-verification timestamp.
Zero data retention is available via Opper Enterprise contract. No training on customer data. EU; DPA available.
Zero data retention is available via Opper Enterprise contract. No training on customer data. US; SCCs; DPA available.
Independent benchmark scores β composite indices for reasoning, coding, and math, plus individual eval scores where available.
Call GPT-5.4 through the Opper gateway with one API key. Let your coding agent set it up, or call it directly β Opper is drop-in compatible with the OpenAI, Anthropic, and Google AI SDKs.
Copy this and paste it into your coding agent β Claude Code, Cursor, Codex, and more β and it'll wire up Opper for you.
import OpenAI from "openai";const client = new OpenAI({apiKey: process.env.OPPER_API_KEY,baseURL: "https://api.opper.ai/v3/compat",});const completion = await client.chat.completions.create({model: "openai/gpt-5.4",messages: [{ role: "user", content: "Hello" }],});console.log(completion.choices[0].message.content);
Side-by-side on privacy, EU hosting, pricing, and benchmarks.
