Kimi K3 Fast vs GPT-5.3 Chat
GPT-5.3 Chat is cheaper on output tokens, while Kimi K3 Fast offers a larger context window. Choose Kimi K3 Fast or GPT-5.3 Chat based on the trade-off between cost, context, and the benchmarks that matter for your use case.
| Spec | Kimi K3 Fast | GPT-5.3 Chat |
|---|---|---|
| Provider | Vercel AI Gateway | Vercel AI Gateway |
| Input / 1M tokens | $4.50 | $1.75 |
| Output / 1M tokens | $22.50 | $14.00 |
| Context window | 1M | 128K |
| Parameters | — | — |
| Open weights | Yes | No |
| Released | Jul 2026 | Mar 2026 |
FAQ
Pricing is indicative — confirm with the provider before production use. Highlighted values indicate the better figure for that row.