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StepFun

StepFun 3.5 Flash

StepFun 3.5 Flash is an open-source sparse MoE reasoning model from StepFun with 196B total parameters and about 11B active per token. It supports a context window of 262.1K tokens and a max output of 262.1K tokens per request.

ReasoningTool UseImplicit Caching
index.ts
import { streamText } from 'ai'


const result = streamText({
  model: 'stepfun/step-3.5-flash',
  prompt: 'Why is the sky blue?'
})
OverviewAboutProvidersThroughputLatencyUptimeStatusSimilarFAQ

Providers

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Provider
Context
Latency
Throughput
Input
Output
Cache
Web Search
Per Query
Capabilities
ZDR
No Training
Release Date
DeepInfra
Legal:Terms
•
Privacy
262K
0.3s
183tps
$0.09/M$0.30/M
Read:$0.02/M
Write:—
——
+1
01/29/2026