Step 2 16K
StepFun · → text
Input$2 /M
Output$2 /M
← ModelsStep 2 16KStep 5 Preview
Step 2 16K vs Step 5 Preview
Compare Step 2 16K from StepFun and Step 5 Preview from StepFun on key metrics including benchmarks, price, context length, and other model features. Access both models and hundreds of others through the AIHubMix API.
Step 2 16KStep 5 Preview+ Add model · 2/4
Step 5 Preview
StepFun · text, image, video → text
Step 5 Preview is StepFun's next-generation flagship base model designed for real-world tasks, with a focus on programming and professional expertise.
Input$1.08 /M
Output$3.0888 /M
Cache read$0.054 /M
Pricing & Specifications
Prices are per million tokens. Time to First Token and throughput are rolling averages measured on AIHubMix.
Step 2 16K
Step 5 Preview
Input /M
$2
$1.08
Output /M
$2
$3.0888
Cache read /M
-
$0.054
Context length
0
1,000,000
Max output
0
64,000
Time to First Token
-
3.6 s
Throughput
-
45.4 tok/s
Modalities
textimagevideo
Supported Parameters
API Formats
Released
January 1, 2025
September 20, 2026
Promotional prices show the discounted rate; see each model page for promotion windows.
Activity Past 30 Days
Daily traffic served through AIHubMix — how demand for each model is trending.
step-2-16kstep-5-preview
Tokens / day
-
Requests / day
-
Performance Past 3 Days
Measured on real AIHubMix traffic, hourly buckets. Gaps mean no traffic in that hour.
step-2-16kstep-5-preview
Throughput (tok/s)
-
TTFT (s)
-
Uptime (%)
-
LMArena Benchmarks
LMArena ratings by capability (Bradley-Terry, commonly called Elo). Higher is better.
Text
step-2-16kstep-5-preview
1280134014001460
Overall
13341447
Coding
13721372
Math
13131313
Hard prompts
13381338
Instruction following
13161316
Multi-turn
13071307
Creative writing
13371337
Longer query
13421342
Chinese
13651365
English
13551355
Source: LMArena (arena.ai) leaderboard, imported by AIHubMix. Models without published ratings are omitted per chart.
Cost calculator
Estimate your monthly bill for the same workload on each model.
Step 5 Preview
$111 /mo
Step 2 16K
$150 /mo
Monthly = daily × 30. Discounted rates applied where a promotion is active.
FAQ
Which is cheaper: Step 2 16K, Step 5 Preview?
Step 2 16K: $2/M output tokens; Step 5 Preview: $3.0888/M. Use the cost calculator above to estimate your own workload.
Can I call Step 2 16K and Step 5 Preview with the same API key?
Yes. AIHubMix serves every model on this page behind one OpenAI-compatible endpoint, so switching between them is a one-line change to the model field — no second account, key or SDK.
Popular comparisons
Related model match-ups readers also look at.
