GPT-5.2 vs Seed 1.5-VL

GPT-5.2

OpenAI

GPT-5.2, released by OpenAI on December 11, 2025, is a large language model from the GPT-5 family that improves on GPT-5 in general intelligence, long-context understanding, agentic tool-calling, and vision. It features a 400K token context window, 128K maximum output tokens, and a knowledge cutoff of August 2025. GPT-5.2 targets long-context coding tasks, extended document analysis, and complex agentic workflows requiring reliable instruction following.

ByteDance

Seed1.5-VL, released by ByteDance Seed on May 15, 2025, is a vision-language foundation model composed of a 532M-parameter vision encoder and a Mixture-of-Experts language model with 20 billion active parameters. It was pretrained on over 3 trillion multimodal tokens and achieved state-of-the-art performance on 38 out of 60 public VLM benchmarks at release. Seed1.5-VL targets complex visual reasoning, OCR, video comprehension, 3D spatial understanding, and multimodal agentic tasks.