Models

GPT 5 Nano vs Kimi K3

Compare GPT 5 Nano from OpenAI 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.

OpenAIGPT 5 NanoMoonshot AIKimi K3
OpenAI logo
GPT 5 Nano
OpenAI · text, image → text

GPT-5-Nano is the smallest and fastest variant in the GPT-5 system, designed specifically for developer tools and environments that demand rapid interactions and ultra-low latency. While it offers a more lightweight solution with limited reasoning depth compared to its larger counterparts, GPT-5-Nano excels in core capabilities such as instruction-following and maintaining critical safety features. As the successor to GPT-4.1-nano, it provides an optimal choice for cost-sensitive or real-time applications, where efficiency and speed are paramount. Particularly well-suited for summarization and classification tasks, GPT-5-Nano is a powerful tool for developers needing a swift, reliable AI model for streamlined processes.

Input$0.05 /M
Output$0.40 /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$3.00 /M
Output$15.00 /M

Pricing & Specifications

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

GPT 5 Nano
Kimi K3
Input /M
$0.05
$3.00
Output /M
$0.40
$15.00
Cache read /M
$0.01
$0.30
Context length
400,000
1,048,576
Max output
128,000
1,048,576
Time to First Token
5.1 s
0.9 s
Throughput
93.8 tok/s
73.1 tok/s
Modalities
textimage
textimagevideo
Supported Parameters
thinkingtoolsfunction callingstructured outputs
thinkingfunction callingstructured outputs
API Formats
Released
-
-

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.

gpt-5-nanokimi-k3

Tokens / day

-

Requests / day

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Performance Past 3 Days

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

gpt-5-nanokimi-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
gpt-5-nanokimi-k3
1220132014201520
Overall
13371486
Coding
13821531
Math
13451345
Hard prompts
13541505
Instruction following
13261479
Multi-turn
13231499
Creative writing
12481470
Longer query
13291502
Chinese
13781527
English
13441491

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.

GPT 5 Nano
$9.00 /mo
Kimi K3
$405 /mo

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

FAQ

Which is cheaper: GPT 5 Nano, Kimi K3?

GPT 5 Nano: $0.40/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; GPT 5 Nano: 1382 (LMArena coding leaderboard).

Which responds faster?

Kimi K3: 0.9s 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?

GPT 5 Nano accepts 400,000 and Kimi K3 accepts 1,048,576 input tokens. Maximum output per request is 128,000 tokens on GPT 5 Nano and 1,048,576 tokens on Kimi K3.

Which one generates tokens faster?

GPT 5 Nano at 93.8 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?

GPT 5 Nano accepts text and image input and supports thinking, 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 GPT 5 Nano 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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