GPT-5.5 Pro API Enterprise Guide: $30 per Million Tokens, Highest Accuracy Tier
GPT-5.5 Pro는 OpenAI가 2026년 4월 24일 출시한 최고 정확도 API 티어로, GPQA Diamond 93.6%, BrowseComp 90.1%를 기록하며 복잡한 엔터프라이즈 워크플로우에서 이전 세대 대비 일관된 우위를 보여준다. 입력 $30/M, 출력 $180/M 토큰이라는 프리미엄 가격에도 불구하고, 40% 적은 추론 토큰 소비 덕분에 실질 비용 증가는 약 20% 수준에 그친다. What Is GPT-5.5 Pro? OpenAI’s Highest Accuracy API Tier Explained GPT-5.5 Pro is OpenAI’s top-tier reasoning model, designed to spend more compute per query to deliver the highest-accuracy outputs available via the API as of April 2026. Unlike the standard GPT-5.5 tier — which balances speed and cost for general-purpose tasks — GPT-5.5 Pro is tuned to “think harder” by default, burning additional reasoning tokens to reduce error rates on ambiguous, multi-step, or high-stakes problems. It ships with a 1M-token context window and is accessible through both the Responses API and Chat Completions API. GPT-5.5 Pro is reserved for Pro, Business, and Enterprise users in ChatGPT and is available to any API customer with a valid organization key. The model is OpenAI’s direct answer to scenarios where a wrong output carries real-world cost — legal liability, financial error, clinical misjudgement — and where the accuracy premium justifies the pricing premium. The core takeaway: GPT-5.5 Pro is not a general upgrade over GPT-5.5 standard; it is a specialized instrument for tasks where getting it wrong is expensive. ...