Kimi K3 Fast vs GPT 5 Mini
moonshotai/kimi-k3-fast-api · openai/gpt-5-mini
As of November 5, 2026, GPT 5 Mini is the cheaper API on UberLLM: $0.0616 per million input tokens and $0.4926 per million output, versus $3.55 / $17.77 for Kimi K3 Fast, about 97% less when output is 3 tokens for every input token. These are the best prices on the market right now. Both work with one OpenAI-compatible key and UberLLM adds no fee. Choose GPT 5 Mini to cut cost; choose Kimi K3 Fast when context size wins. Kimi K3 Fast carries the larger context window (1,000,000 vs 400,000 tokens), which can matter for long-document work.
Kimi K3 Fast vs GPT 5 Mini, side by side
| Spec | Kimi K3 Fast | GPT 5 Mini |
|---|---|---|
| Price · input / 1M | $3.55 | $0.0616 |
| Price · output / 1M | $17.77 | $0.4926 |
| Context length | 1,000,000 | 400,000 |
| Max output tokens | 131,072 | 128,000 |
| Input modalities | text, image | text, image |
| Output modalities | text | text |
| Tools / functions | Yes | Yes |
| Vision (image input) | Yes | Yes |
| Reasoning | Yes | Yes |
| % off list | 21% off | 75.4% off |
Best prices on UberLLM right now. No UberLLM fee on requests; adding credit by card costs 5.5% + $0.50. Updated November 5, 2026. A price more than 70% below list is what buyers were billed, not an error. Why so cheap?
Kimi K3 Fast vs GPT 5 Mini — FAQ
Is Kimi K3 Fast or GPT 5 Mini cheaper?
GPT 5 Mini is cheaper on a blended token mix, by about 97%. A request costs what its provider charged, UberLLM adds no fee, and every request is listed with its cost in Activity.
What's the price difference between Kimi K3 Fast and GPT 5 Mini?
Kimi K3 Fast: $3.55 in / $17.77 out per 1M tokens. GPT 5 Mini: $0.0616 in / $0.4926 out per 1M tokens. That's roughly a 97% blended difference. Prices are live; UberLLM adds no fee.
Can I use both Kimi K3 Fast and GPT 5 Mini with one API?
Yes. Both are served through a single OpenAI-compatible endpoint — set the base URL to https://api.uberllm.dev/v1 and your UberLLM key, then switch between them by changing the model id. Anthropic SDKs work via https://api.uberllm.dev/v1/messages.