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StepFun: Step 3.5 Flash (free)

StepFun·Released 2026-01-29
256K ctx

About

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....

Pricing

Input

$0.00

per 1M tokens

Output

$0.00

per 1M tokens

Blended

$0.00

per 1M tokens

Cheaper than 92% of models. Median price is $0.54/1M tokens.

Cost Calculator

Tokens per day1M
100K100M

Daily

$0.00

Monthly

$0.00

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Performance

Context Window

256K

tokens

Larger than 58% of models

Max Output

256K

tokens

100% of context

Context Window Comparison

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