kimi-k3
Moonshot AI · text, image, video → text
Kimi K3 is Kimi’s flagship model for long-horizon coding and end-to-end knowledge work, with a 1M-token context window and industry-leading intelligence.
Input$3.00 /M
Output$15.00 /M
← Modelskimi-k3
step-3.5-flash
kimi-k3 vs step-3.5-flash
Output tokens cost $15.00 per million on kimi-k3 and $0.33 per million on step-3.5-flash. Input tokens cost $3.00 per million on kimi-k3 and $0.11 per million on step-3.5-flash. Cached input tokens are billed at $0.30 per million on kimi-k3 and $0.11 per million on step-3.5-flash. Context lengths are 1,048,576 tokens on kimi-k3 and 256,000 tokens on step-3.5-flash. On the LMArena coding leaderboard kimi-k3 scores 1531 and step-3.5-flash scores 1451.
kimi-k3step-3.5-flash+ Add model · 2/4
step-3.5-flash
StepFun · text, image → text
step-3.5-flash is stepfun's flagship inference model, designed for high-complexity tasks that require deep reasoning and fast execution. It excels at decomposing multi-step problems, performing tool calls, and maintaining consistency across massive datasets. It is the preferred choice for complex workloads such as long-context agents, advanced software engineering, and end-to-end research automation.
Input$0.11 /M
Output$0.33 /M
Pricing & Specifications
Prices are per million tokens. Time to First Token and throughput are rolling averages measured on AIHubMix.
kimi-k3
step-3.5-flash
Input /M
$3.00
$0.11
Output /M
$15.00
$0.33
Cache read /M
$0.30
$0.11
Context length
1,048,576
256,000
Max output
1,048,576
0
Time to First Token
12.9 s
-
Throughput
18.8 tok/s
-
Modalities
textimagevideo
textimage
Supported Parameters
thinkingfunction callingstructured outputs
API Formats
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.
kimi-k3step-3.5-flash
Tokens / day
-
Requests / day
-
Performance Past 3 Days
Measured on real AIHubMix traffic, hourly buckets. Gaps mean no traffic in that hour.
kimi-k3step-3.5-flash
Throughput (tok/s)
-
TTFT (s)
-
Uptime (%)
-
LMArena Benchmarks
LMArena ratings by capability (Bradley-Terry, commonly called Elo). Higher is better.
Text
kimi-k3step-3.5-flash
13201380144015001560
Overall
13951486
Coding
14511531
Math
14061406
Hard prompts
14141505
Instruction following
13861479
Multi-turn
13971499
Creative writing
13451470
Longer query
14051502
Chinese
14371527
English
14101491
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-3.5-flash
$11.55 /mo
kimi-k3
$405 /mo
Monthly = daily × 30. Discounted rates applied where a promotion is active.
FAQ
Which is cheaper: kimi-k3, step-3.5-flash?
step-3.5-flash: $0.33/M output tokens; kimi-k3: $15.00/M. Use the cost calculator above to estimate your own workload.
How do their coding arena scores compare?
kimi-k3: 1531; step-3.5-flash: 1451 (LMArena coding leaderboard).
How large is each context window?
kimi-k3 accepts 1,048,576 and step-3.5-flash accepts 256,000 input tokens.
What inputs and capabilities does each model support?
kimi-k3 accepts text, image and video input and supports thinking, function calling and structured outputs; step-3.5-flash accepts text and image input.
Can I call kimi-k3 and step-3.5-flash 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.
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