Comprehensive side-by-side LLM comparison
Seed 1.5-VL supports multimodal inputs. Both models have their strengths depending on your specific coding needs.
OpenAI
GPT-5.1 Codex Max, released by OpenAI in November 2025, is an enhanced coding variant from the GPT-5.1 Codex line, designed for more complex software engineering tasks requiring additional reasoning depth. It targets large-scale code generation, automated refactoring, and sophisticated agentic development workflows.
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.
5 months newer
Seed 1.5-VL
ByteDance
2025-05-15

GPT-5.1 Codex Max
OpenAI
2025-11
Available providers and their performance metrics
GPT-5.1 Codex Max
Seed 1.5-VL
GPT-5.1 Codex Max
Seed 1.5-VL