Kimi K2 Thinking vs GPT-5.4 nano

Kimi K2 Thinking versus GPT-5.4 nano specifications and price.
metric	Kimi K2 Thinking	GPT-5.4 nano
Input / 1M	$0.60	$0.20
Output / 1M	$2.50	$1.25
Context	262K	400K
Cost @ typical workload	$430/mo	$185/mo
Modality	Text only	text + image
Price source	routed	list
Provider	Moonshot	OpenAI

Which should you pick?

On a typical workload, GPT-5.4 nano costs $185/mo against Kimi K2 Thinking's $430/mo — roughly 2.3× cheaper. But the ranking depends on your output-to-input ratio: output is the pricier direction for both, so an output-heavy job (code generation, long answers) widens the gap while an input-heavy one (summarization, retrieval) narrows it. If you need to fit more in a single prompt, GPT-5.4 nano has the larger 400K-token window (~600 pages). Only GPT-5.4 nano accepts image input — decisive if your prompts include images.

These are list and routed market prices, not measured outcomes. Two models at the same rate can still cost different amounts to finish the same task, because verbose or reasoning-heavy models emit more tokens. That gap is exactly what measured cost-per-task captures.

Frequently asked questions

Is Kimi K2 Thinking or GPT-5.4 nano cheaper?

For a typical workload (1,500 input + 500 output tokens × 200,000 requests/month), GPT-5.4 nano costs $185/mo versus $430/mo for Kimi K2 Thinking — about 2.3× less. Because output is priced higher than input, the winner can flip if your workload writes much more or less than this; check your own numbers in the calculator.

What's the main difference between Kimi K2 Thinking and GPT-5.4 nano?

On price, Kimi K2 Thinking is $0.60/$2.50 per 1M (in/out) and GPT-5.4 nano is $0.20/$1.25. GPT-5.4 nano has the larger context window at 400K tokens. GPT-5.4 nano also accepts image input, while Kimi K2 Thinking is text-only.

More comparisons

Kimi K2 Thinking and GPT-5.4 nano — full specs and price history.
API cost calculator — compare on your own workload.
All comparisons — the full head-to-head index.