GPT-5.1

GPT-5.2

OpenAI

GPT-5.2 is OpenAI's flagship frontier model series designed for professional knowledge work, advanced coding, and agentic workflows. Released in December 2025 as a response to competitive pressures, it features a massive 400,000-token context window and a 128,000-token maximum output capacity. The model utilizes a Mixture-of-Experts (MoE) architecture to balance inference efficiency with deep reasoning capabilities. It is available in three variants—Instant, Thinking, and Pro—each optimized for different points on the latency-intelligence curve. GPT-5.2 demonstrates state-of-the-art performance in tool calling reliability (98.7%), coding (SWE-Bench Verified 80.0%), and long-context retrieval.

GPT-OSS-120B

OpenAI

GPT-OSS-120B is a state-of-the-art open-weight language model that delivers strong real-world performance at low cost. This 120 billion parameter mixture-of-experts model achieves near-parity with OpenAI o4-mini on core reasoning benchmarks while running efficiently on a single 80 GB GPU. It was trained using reinforcement learning and techniques informed by OpenAI's most advanced internal models, including o3 and other frontier systems.

GPT-OSS-20B

OpenAI

GPT-OSS-20B is a medium-sized open-weight language model that delivers similar results to OpenAI o3‑mini on common benchmarks and can run on edge devices with just 16 GB of memory. This makes it ideal for on-device use cases, local inference, or rapid iteration without costly infrastructure. Despite its smaller size, it demonstrates strong performance on reasoning tasks, tool use, and competition mathematics.