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Provider analysis

StepFun

Chinese AI lab publishing open-weight models including Step-3.5-Flash (199B), Step3-VL vision-language models, and Step-Audio models.

Last verified: 2026-03-29Confidence: HighPrimary sources: 2

This provider page blends full-profile entries with broader verified listings. Use it to separate deeply evaluated flagship models from source-backed records that are tracked primarily for market visibility, access data, and freshness coverage.

Headquarters
Beijing, China
Founded
2023
Models tracked
4
Full-profile models
4
Catalog last verified
2026-03-29
Latest model verification
2026-03-29
Newest release tracked
2026-02-16
Confidence
High
Access mix
open-weight, self-hosted
API models
0

Tracked models available through provider-managed APIs.

Open-weight models
4

Models with downloadable weights or self-hosted distribution paths.

Primary source links
12

Total source references attached across this provider catalog.

Provider sources

Official links used to verify the provider profile and platform coverage.

Last verified: 2026-03-29

StepFun

Step-3.5-Flash

Step

StepFun's 199B parameter Step-3.5-Flash for text generation and reasoning. 91.9K downloads on HuggingFace. Available in BF16, FP8, and GGUF quantizations.

Score 703 sources
textreasoningcodeopen-sourceopen-weightself-hosted
Context
131,072
Input
Not applicable
Output
Not applicable
Coverage
Full profile

StepFun

Step3-VL-10B

Step

StepFun's 10B Step3-VL vision-language model with 211K downloads on HuggingFace. Supports FP8 quantization.

Score 673 sources
textvisionopen-sourceopen-weightself-hosted
Context
131,072
Input
Not applicable
Output
Not applicable
Coverage
Full profile

StepFun

Step-Audio-R1.1

Step

StepFun's 33B Step-Audio-R1.1 for audio-text-to-text generation and understanding.

Score 593 sources
textaudioopen-sourceopen-weightself-hosted
Context
131,072
Input
Not applicable
Output
Not applicable
Coverage
Full profile

StepFun

NextStep-1.1

Step

StepFun's 15B NextStep-1.1 for text-to-image generation. Supports image editing and modification based on text prompts.

Score 423 sources
imagevisionopen-sourceopen-weightself-hosted
Context
512
Input
Not applicable
Output
Not applicable
Coverage
Full profile