Comprehensive side-by-side LLM comparison
Gemini 3.1 Pro leads with 6.2% higher average benchmark score. Gemini 3.1 Pro supports multimodal inputs. Overall, Gemini 3.1 Pro is the stronger choice for coding tasks.
Google DeepMind
Gemini 3.1 Pro is a multimodal language model from Google DeepMind, released in preview in February 2026 as a point-version upgrade to Gemini 3 Pro focused on improving reasoning depth, factual grounding, and coding and agentic task performance. The model accepts text, images, video, audio, and PDFs as inputs across a 1M token context window, extending the multimodal breadth of the Gemini 3 series with a companion endpoint specifically optimized for custom tool use in agentic pipelines. Google describes it as built to refine the reliability and performance of the Gemini 3 Pro series, reflecting an incremental engineering iteration rather than an architectural overhaul.
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.
17 days newer
Step-3.5-Flash
StepFun
2026-02-02

Gemini 3.1 Pro
Google DeepMind
2026-02-19
Context window and performance specifications
Average performance across 1 common benchmarks
Gemini 3.1 Pro
Step-3.5-Flash
Performance comparison across key benchmark categories
Gemini 3.1 Pro
Step-3.5-Flash
Gemini 3.1 Pro
2025-01
Available providers and their performance metrics
Gemini 3.1 Pro
Step-3.5-Flash
Gemini 3.1 Pro
Step-3.5-Flash
Gemini 3.1 Pro
Step-3.5-Flash