How much does Step 3.5 Flash cost on Zeplik?

Input tokens cost 1.1 credits per million and output tokens 3.3 credits per million (1 credit = $0.10; the raw provider rates are $0.10 and $0.30 per million). New accounts start with free credits.

How long can a conversation with Step 3.5 Flash be?

Step 3.5 Flash has a 262K-token context window (262,144 tokens), which covers the conversation plus any documents you attach.

Does Step 3.5 Flash support images and tools?

Step 3.5 Flash is text-only and supports tool calling.

Step 3.5 Flash

Fast and lightTools

StepFun · Released January 2026

Step 3.5 Flash is StepFun's most capable open-source foundation model. Built on a sparse Mixture of Experts (MoE) architecture, it selectively activates only 11B of its 196B parameters per token....

Facts and pricing

Provider: StepFun
Context window: 262K tokens
Input price: 1.1 credits / 1M tokens ($0.10 raw)
Output price: 3.3 credits / 1M tokens ($0.30 raw)
Vision (image input): No
Tool calling: Yes
Extended reasoning: No

Credits are what Zeplik bills: 1 credit = $0.10, computed from the raw provider rate with a 1.10x margin. Raw prices shown per 1M tokens.

Try Step 3.5 Flash now

Or open Zeplik with Step 3.5 Flash already selected

What Step 3.5 Flash is best for

High-volume everyday tasks where speed and cost matter: summaries, drafts, quick questions
Long documents: the 262K-token window holds lengthy reports, contracts or papers whole
Tool use and agents: reliably calls functions, so it can search, run skills and drive workflows

StepFun family

Model	Context	Input cr/M	Output cr/M	Released
Step 3.7 Flash	256K	2.2	12.7	May 2026
Step 3.5 Flash	262K	1.1	3.3	January 2026

Frequently asked questions

What is Step 3.5 Flash?: Step 3.5 Flash is an AI model by StepFun. Step 3.5 Flash is StepFun's most capable open-source foundation model. Built on a sparse Mixture of Experts (MoE) architecture, it selectively activates only 11B of its 196B parameters per token....
How much does Step 3.5 Flash cost on Zeplik?: Input tokens cost 1.1 credits per million and output tokens 3.3 credits per million (1 credit = $0.10; the raw provider rates are $0.10 and $0.30 per million). New accounts start with free credits.
How long can a conversation with Step 3.5 Flash be?: Step 3.5 Flash has a 262K-token context window (262,144 tokens), which covers the conversation plus any documents you attach.
Does Step 3.5 Flash support images and tools?: Step 3.5 Flash is text-only and supports tool calling.

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