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GPT-OSS-20B vs Step-3.5-Flash
Comprehensive side-by-side LLM comparison
. Both models have their strengths depending on your specific coding needs.
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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.
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StepFun
Step-3.5-Flash, released by StepFun on February 2, 2026, is a Mixture-of-Experts large language model with 197 billion total parameters and approximately 11 billion active parameters per inference. It features a 256K token context window using a 3:1 sliding-window-to-full-attention ratio, processing 100–350 tokens per second. Step-3.5-Flash targets agentic tasks, coding workflows, and open-source deployments requiring frontier reasoning capabilities with efficient inference, under an Apache 2.0 license.
6 months newer
GPT-OSS-20B
OpenAI
2025-08-05
Step-3.5-Flash
StepFun
2026-02-02
Performance Metrics
Context window and performance specifications
Provider Availability & Performance
Available providers and their performance metrics
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GPT-OSS-20B
1 providers
Hugging Face
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Step-3.5-Flash
0 providers
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GPT-OSS-20B
Avg Score:0.0%
Providers:1
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Step-3.5-Flash
Avg Score:0.0%
Providers:0