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Gemini 2.5 Flash Preview 09 2025 vs Kimi K3

Compare Gemini 2.5 Flash Preview 09 2025 from Google and Kimi K3 from Moonshot AI on key metrics including benchmarks, price, context length, and other model features. Access both models and hundreds of others through the AIHubMix API.

GoogleGemini 2.5 Flash Preview 09 2025Moonshot AIKimi K3
Google logo
Gemini 2.5 Flash Preview 09 2025
Google · text, image, video, audio → text

This latest 2.5 Flash model comes with improvements in two key areas we heard consistent feedback on: Better agentic tool use: We've improved how the model uses tools, leading to better performance in more complex, agentic and multi-step applications. This model shows noticeable improvements on key agentic benchmarks, including a 5% gain on SWE-Bench Verified, compared to our last release (48.9% → 54%). More efficient: With thinking on, the model is now significantly more cost-efficient—achieving higher quality outputs while using fewer tokens, reducing latency and cost (see charts above).

Input$0.3 /M
Output$2.499 /M
Cache read$0.03 /M
Moonshot AI logo
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$2.84 /M
Output$14.2 /M
Cache read$0.284 /M

Pricing & Specifications

Prices are per million tokens. Time to First Token and throughput are rolling averages measured on AIHubMix.

Gemini 2.5 Flash Preview 09 2025
Kimi K3
Input /M
$0.3
$2.84
Output /M
$2.499
$14.2
Cache read /M
$0.03
$0.284
Context length
1,048,576
1,048,576
Max output
65,536
1,048,576
Time to First Token
0.4 s
0.7 s
Throughput
144.3 tok/s
73.1 tok/s
Modalities
textimagevideoaudio
textimagevideo
Supported Parameters
toolsfunction callingstructured outputs
thinkingfunction callingstructured outputs
API Formats
Released
September 25, 2025
July 16, 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.

gemini-2.5-flash-preview-09-2025kimi-k3

Tokens / day

-

Requests / day

-

Performance Past 3 Days

Measured on real AIHubMix traffic, hourly buckets. Gaps mean no traffic in that hour.

gemini-2.5-flash-preview-09-2025kimi-k3

Throughput (tok/s)

-

TTFT (s)

-

Uptime (%)

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LMArena Benchmarks

LMArena ratings by capability (Bradley-Terry, commonly called Elo). Higher is better.

Text
gemini-2.5-flash-preview-09-2025kimi-k3
13601400144014801520
Overall
14041487
Coding
14281428
Math
14121412
Hard prompts
14201420
Instruction following
14021402
Multi-turn
14001400
Creative writing
13831383
Longer query
14171417
Chinese
14481448
English
14111411

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.

Gemini 2.5 Flash Preview 09 2025
$55.49 /mo
Kimi K3
$383 /mo

Monthly = daily × 30. Discounted rates applied where a promotion is active.

FAQ

Which is cheaper: Gemini 2.5 Flash Preview 09 2025, Kimi K3?

Gemini 2.5 Flash Preview 09 2025: $2.499/M output tokens; Kimi K3: $14.2/M. Use the cost calculator above to estimate your own workload.

Which responds faster?

Gemini 2.5 Flash Preview 09 2025: 0.4s time to first token measured on AIHubMix; see the live performance charts above for how each model behaves across the day.

How large is each context window?

Gemini 2.5 Flash Preview 09 2025 accepts 1,048,576 and Kimi K3 accepts 1,048,576 input tokens. Maximum output per request is 65,536 tokens on Gemini 2.5 Flash Preview 09 2025 and 1,048,576 tokens on Kimi K3.

Which one generates tokens faster?

Gemini 2.5 Flash Preview 09 2025 at 144.3 tok/s and Kimi K3 at 73.1 tok/s, measured as output throughput on AIHubMix — a separate metric from time to first token.

What inputs and capabilities does each model support?

Gemini 2.5 Flash Preview 09 2025 accepts text, image, video and audio input and supports tool calling, function calling and structured outputs; Kimi K3 accepts text, image and video input and supports thinking, function calling and structured outputs.

Can I call Gemini 2.5 Flash Preview 09 2025 and Kimi K3 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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