Comprehensive side-by-side LLM comparison
GPT-5.1 leads with 8.0% higher average benchmark score. GPT-5.1 supports multimodal inputs. Overall, GPT-5.1 is the stronger choice for coding tasks.
OpenAI
GPT-5.1, released by OpenAI in November 2025, is a large language model from the GPT-5 family that delivers incremental improvements in reasoning, instruction following, and multimodal understanding over GPT-5. It features a 400K token context window and targets general-purpose development, long-context analysis, and agentic workflows.
OpenAI
GPT-OSS-20B is an open-weight large language model with 20 billion parameters from OpenAI's open-source model initiative. It targets deployments requiring a smaller, efficient model that can run on consumer or mid-tier hardware while maintaining strong reasoning and coding capabilities relative to its size.
2 months newer

GPT-OSS-20B
OpenAI
2025-08-05

GPT-5.1
OpenAI
2025-11
Context window and performance specifications
Average performance across 1 common benchmarks
GPT-5.1
GPT-OSS-20B
Performance comparison across key benchmark categories
GPT-5.1
GPT-OSS-20B
Available providers and their performance metrics
GPT-5.1
GPT-OSS-20B
Hugging Face
GPT-5.1
GPT-OSS-20B
GPT-5.1
GPT-OSS-20B