StepFun Open Platform

Analyze long documents, multiple source materials, and conversation history within a 1M-token context.Typical tasks: cross-document question answering and research material organization.

Compare the positioning and capabilities of Step 5 Preview, Step 3.7 Flash, and Step 3.5 Flash.

The page describes the Step API as a stable, high-performance tool for easy integration with leading AI models.

GitHubRepository owner

StepFun’s lightweight AI model, **Step 3.5 Flash**, delivers competitive performance against larger rivals in efficiency and reasoning tasks. The model targets cost-effective AI deployment in China’s expanding market. StepFun positions it as a disruptive force in the AI landscape.

Feb 2026South China Morning PostNews article

StepFun secures over RMB 5 billion (USD 700 million) in a Series B+ funding round, closing in six months. The round’s scale and rapid completion highlight investor confidence amid AI industry consolidation. The company’s growth trajectory and strategic positioning attract significant capital despite competitive pressures.

Jan 2026KrASIANews article

Stepfun secures **$719 million** in Series B+ funding to accelerate AI deployment beyond model development. The capital supports scaling foundation models, deploying AI agents, and building industry-specific AI solutions. This positions Stepfun among China’s top-funded private AI startups in 2024, reflecting a broader industry pivot toward practical applications.

Jan 2026AsiaTechDaily - Asia's Leading Tech and Startup Media PlatformNews article