WhichAI / Models / Step 3.5 Flash

Step 3.5 Flash

· verified October 13, 2026

public paid api open-weights local

Provider

Statuspublic

AA Intelligence Index17 (official, read October 13, 2026)

Released2026-01-29

Context window262K

ModalitiesText

API price $/1M (in / out)$0.1 / $0.3 (OpenRouter)

Speedn/a

AccessAPI $0.1/$0.3 per 1M tokens on OpenRouter · open weights · listed January 29, 2026

In one line

Step 3.5 Flash by StepFun, measured by Artificial Analysis at 17 on the Intelligence Index. Added to WhichAI automatically from live data on October 13, 2026: no editorial review yet, so judge it by the numbers, not by a verdict. OpenRouter's description: “Step 3.5 Flash is StepFun's most capable open-source foundation model.”

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Gemma 4 26B A4B (Google) · AA 16.7API $0.09/$0.3 per 1M tokens on OpenRouter · free route on OpenRouter (google/gemma-4-26b-a4b-it:free) · open weights · listed April 3, 2026
DeepSeek V3.2 Exp (DeepSeek) · AA 16.6API $0.27/$0.41 per 1M tokens on OpenRouter · open weights · listed September 29, 2025

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Artificial Analysis Intelligence Index, official scale (the number published on artificialanalysis.ai), relayed by OpenRouter and refreshed automatically: last read October 13, 2026. 210 models carry a current official measurement. A value marked ~ is converted from an earlier snapshot because no current measurement is published; an unmeasured model is never ranked. Context, price, modality and listing dates come from the public OpenRouter model list (refreshed automatically on the live site; static copy retrieved October 3, 2026) and vendor pages. Missing values are not published or not yet verified - shown as -. Sources are linked inside the app (the Ranking chapter and About > Methodology).