GPT-5 Mini vs Seed 1.5-VL

GPT-5 Mini

OpenAI

GPT-5 mini, released by OpenAI in August 2025, is a smaller variant from the GPT-5 family that inherits GPT-5's unified reasoning architecture and multimodal capabilities at a reduced inference cost. It targets high-volume production use cases requiring a balance of intelligence and response speed, offering GPT-5 capabilities for applications where full GPT-5 inference costs are a concern.

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.