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#401

Step 3.5 Flash

Stepfun Release: 2026-02-01 Tested on: 2026-05-08 15:30 stepfun/step-3.5-flash::none
196B total (11B active)MoEOpen source
(medium) (none)

Summary

Step 3.5 Flash scores 1.9 on AI BENCHY and ranks #401. It has 10.0 reliability, a 26.1% pass rate, $0.020 total cost, and 39.03s average response time.

What makes Step 3.5 Flash unique: It stands out most in Anti-AI Tricks, where it ranks #1, while Data parsing and extraction is its weakest area at #11. It uses unusually many reasoning tokens, which can help explain its slower or more expensive runs.

Archived model: this model is no longer updated or tested on new tests.

Model facts

Researched on 2026-08-12

Reported
Parameters
196B total (11B active)
Architecture
MoE
Availability
Open source
License
Apache-2.0
Parameter source Availability source

Score

1.9

Consistency

5.2

Reliability

10.0

Total Cost (Current Price)

$0.020

Total Output Tokens

64,795

Total Input Tokens

1,971

Input Price

$0.100 / 1M

Output Price

$0.300 / 1M

Cache Read Price

N/A

Cache Write Price

N/A

Cache prices apply to input tokens. Reads reuse cached prompts; writes store them and can cost extra. Output tokens use the output price.

Tests Correct

Wrong Tests: 6

Attempt pass rate: 26.1%

Flaky tests

0

Flaky tests had mixed outcomes across runs (at least one pass and one fail).

Response Time (avg)

39.03s

Response Time (max): 114.12s

Response Time (total): 312.26s

API error: 4 Did not follow instructions: 1 Wrong answer: 1

Hamster playing table tennis

Prompt: Create a detailed SVG illustration of a hamster playing table tennis.

#401 Step 3.5 Flash

none
Cost
$0.005
Time
156.3s
Tokens
13,887 tok

Run history

Tested on Score Reliability Tests Correct Total Cost Compare
2026-05-08 15:30 New test added 1.9 10.0 $0.020 Current run
2026-04-11 01:44 First recorded run 3.0 N/A $0.000 Compare

This run used a different benchmark suite. Keep suite changes in mind when reading historical movement.

Price History

Historical pricing data for this model from OpenRouter.

Date Input Price Output Price Cache Read Price Cache Write Price
2026-06-04 15:40 $0.090 / 1M $0.300 / 1M N/A N/A
2026-06-30 21:25 $0.100 / 1M $0.300 / 1M N/A N/A

Charts

Choose the first model, then click a second model to open a side-by-side page.

Total Output Tokens

Score vs Total Output Tokens

Category Breakdown

Category Score Consistency Tests Correct
Agentic 0.0 0.0
Anti-AI Tricks 10.0 10.0
Coding 1.0 3.3
Combined 1.5 5.0
Data parsing and extraction 1.5 5.0
Domain specific 3.3 3.3
General Intelligence 4.0 10.0
Instructions following 5.0 5.0
Puzzle Solving 0.0 0.0
Tool Calling 3.0 10.0
Trivia 3.0 10.0

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