StepFun AI models
4 current StepFun models on AIblogly, and 2 that StepFun has retired. The newest is Step 5 Preview, released 20 September 2026. The highest StepFun model on LMArena’s text leaderboard is Step 5 Preview, at rank 84.
Current StepFun models
| Model | Type | Released | Price | LMArena rank |
|---|---|---|---|---|
| Step 5 Preview | Text | 20 September 2026 | $1 / $2.70 per 1M tokens | #84 |
| Step 3.7 Flash | Text | 29 May 2026 | $0.20 / $1.15 per 1M tokens; $0.04 cached input | — |
| Step 3.5 Flash | Text | — | $0.1 / $0.3 per 1M tokens | #174 |
| Step 3 | Text | — | $0.57 / $1.42 per 1M tokens | #220 |
Retired StepFun models
StepFun no longer offers these through its API. Dates are the ones StepFun states; the replacement is the model it points users to.
| Model | Released | Retired | Description | Replacement |
|---|---|---|---|---|
| Step 1O Turbo 202506 | — | Not on StepFun’s API price list (checked 28 Oct 2026) | A June 2025 build of StepFun’s Step 1o Turbo. Source | step-1o-turbo-vision |
| Step 2 16K Exp 202412 | — | Not on StepFun’s API price list (checked 28 Oct 2026) | An experimental December 2024 build of StepFun’s Step 2 with a 16K context. Source | Step 3.7 Flash, Step 5 Preview |
Frequently asked questions
What is StepFun's newest AI model?+
Of the StepFun models listed here, the most recently released is Step 5 Preview, released on 20 September 2026.
Which StepFun model ranks highest on LMArena?+
Step 5 Preview, at rank 84 on LMArena's text leaderboard (Elo 1448). The full table is at aiblogly.com/benchmarks.
Which StepFun AI models have been retired?+
Step 1O Turbo 202506 (retired Not on StepFun’s API price list (checked 28 Oct 2026)); Step 2 16K Exp 202412 (retired Not on StepFun’s API price list (checked 28 Oct 2026)).