Step 5 Preview · StepFun

What does Step 5 Preview cost to run in a coding agent?

Step 5 Preview costs about $0.025 per average coding-agent request on our measured traffic, at list prices of $1 per million input and $2.70 per million output tokens. It scores 44 on the Artificial Analysis Intelligence Index, 13th of the 48 models we track. Source: Artificial Analysis (artificialanalysis.ai)

List prices: OpenRouter (vendor endpoint), checked 2026-10-13. Request costs: Standard Compute gateway data, 79,301 coding-agent requests from 75 users, Sep 13 to Oct 12, 2026. How we compute this

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What Step 5 costs per coding-agent request

Cost at list price	Step 5
Prompt under 100K tokens50% of requests, 87% of input cached	$0.012
Prompt of 100K to 272K39% of requests, 88% of input cached	$0.030
Prompt over 272K tokens11% of requests, 86% of input cached	$0.069
Average request	$0.025
100 requests	$2.48
Median session16 requests; a session ends after 10 idle minutes	$0.33
A month of regular usemedian of 20 users active on 5+ days	$35.48

Each logged request priced at the vendor’s list rates for its own token counts, including cache reads and any higher rate for long prompts. Average output: 698 tokens per request.

Step 5 benchmarks, speed and latency

Artificial Analysis	Value	Rank
Intelligence Index10 evaluations, 0 to 100	44	13 of 48
Terminal-Bench 4.0agentic coding in a terminal	33.3%	13 of 39
Output speedmedian	90 tokens/s	25 of 44
Time to first answer tokenincludes thinking time	25 s	15 of 44

Source: Artificial Analysis (artificialanalysis.ai). Measured variant: Step 5 Preview, speed on StepFun. Fetched October 13, 2026. Rank is among the models on this site, older versions included. Artificial Analysis runs Terminal-Bench 4.0 in its own setup, so its scores differ from the tbench.ai leaderboard.

About Step 5 Preview

Step 5 Preview is StepFun's flagship model for agent work, on OpenRouter since October 8, 2026 and served there by StepFun. It is a sparse mixture-of-experts model with 27B active and 600B total parameters, reads text, images and video, and has a 1M-token context with 64K output. Artificial Analysis scores it 44 on its Intelligence Index and 33.3% in its Terminal-Bench 4.0 run, ahead of Gemini 3.8 Flash on both, at about 90 output tokens per second. In our measurements it costs $0.025 per request, about half of Gemini 3.8 Flash. Cline added it to its free model list on October 13. It is still a preview.

Sources: OpenRouter listing · Artificial Analysis · Cline v4.1.24 release notes

Step 5 Preview FAQ

How much does Step 5 Preview cost per coding-agent request?

$0.025 on average at list price, $2.48 per 100 requests, and $0.33 for a median 16-request session. That is 79,301 real coding-agent requests (Sep 13 to Oct 12, 2026) priced at StepFun's list rates; the median request sent 99,534 input tokens, 87% of input was read from cache, and requests returned 698 output tokens on average.

Does Step 5 Preview charge more for long prompts?

No. Step 5 Preview bills the same rate per token up to its 1M-token context window.

How fast is Step 5 Preview?

Artificial Analysis measures Step 5 Preview at 90 output tokens per second, with 25 seconds to the first answer token, thinking time included, on StepFun's API. Source: Artificial Analysis (artificialanalysis.ai).

Is Step 5 Preview good for AI agents?

Mid-priced agent loops that want more capability than a Flash-class model. On our scoring, which is calibrated to public benchmarks, it rates 7.6/10 for agentic ability and 8.2/10 for output quality. Scores above Gemini 3.8 Flash on Artificial Analysis (44 vs 41) and Terminal-Bench 4.0 (33.3% vs 19.7%).

What is Step 5 Preview's context window?

Step 5 Preview has a 1M-token context window, large enough to hold sizeable codebases or document sets in a single run. StepFun is the maker.

Can I self-host Step 5 Preview?

No. Step 5 Preview is a proprietary, hosted-only model from StepFun. You access it through an API, such as OpenRouter, rather than running the weights yourself.

What are the downsides of Step 5 Preview?

The main trade-offs: Still a preview, so behavior and price can change; Only StepFun serves it on OpenRouter, so there is no provider fallback. It's strongest for mid-priced agent loops that want more capability than a Flash-class model.