Kimi K3.1 Pro is $3 cheaper per 1M input tokens (60% lower; 2.5x difference).
API cost decision in 10 seconds
NewKimi K3.1 Pro vs GPT-6 Astra Pro (batch)
Pick Kimi K3.1 Pro for lower cost; pick GPT-6 Astra Pro (batch) only if the larger context window matters more.
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Data confirmed:
Prices normalized to USD per 1M tokens
Sample workload: 1M input + 500K output
Budget verdict
Pick Kimi K3.1 Pro for lower cost; pick GPT-6 Astra Pro (batch) only if the larger context window matters more.
On the standard 1M input plus 500K output workload, Kimi K3.1 Pro is estimated at $7 vs $17.5 for GPT-6 Astra Pro (batch), saving $10.5 (60% lower).
Cost-first pickKimi K3.1 Pro
Context-first pickGPT-6 Astra Pro (batch)
Sample savings$10.560%
10x traffic gap$105
GPT-6 Astra Pro (batch) has more context, but Kimi K3.1 Pro saves $10.5 on the standard workload. At 10x that traffic, the same price gap is about $105. Use the calculator below to replace the sample workload with your own token volume.
Cost sensitivity
Workload Sensitivity
Kimi K3.1 Pro stays cheaper across input-heavy, balanced, and output-heavy sample workloads.
| Workload shape | Token mix | Better pick | Kimi K3.1 Pro | GPT-6 Astra Pro (batch) |
|---|---|---|---|---|
| Input-heavy / RAG | 5M input + 500K output | Kimi K3.1 Pro | $15 | $37.5 |
| Balanced workload | 1M input + 1M output | Kimi K3.1 Pro | $12 | $30 |
| Output-heavy chatbot | 1M input + 5M output | Kimi K3.1 Pro | $52 | $130 |
Kimi K3.1 Pro is $15 cheaper per 1M output tokens (60% lower; 2.5x difference).
GPT-6 Astra Pro (batch) has 1.42K more context (1x larger).
Kimi K3.1 Pro is $10.5 cheaper on the standard workload (60% lower).
Estimate your workload cost
Your Workload Cost
This estimate uses normalized public API pricing per 1M tokens. It is a planning aid, not a billing quote. Verify provider pricing, limits, and terms before production use.
Quick Decision
Kimi K3.1 Pro has the lower input price; Kimi K3.1 Pro has the lower output price; GPT-6 Astra Pro (batch) offers the larger context window. For the 1M input plus 500K output sample, Kimi K3.1 Pro is cheaper for the standard workload.
For a 1M input token plus 500K output token workload, the estimated API cost is $7 for Kimi K3.1 Pro and $17.5 for GPT-6 Astra Pro (batch).
Choose Kimi K3.1 Pro when you care most about lower input-token price, and lower output-token price.
Choose GPT-6 Astra Pro (batch) when you care most about larger context window.
- On the standard 1M input plus 500K output workload, Kimi K3.1 Pro is estimated at $7 vs $17.5 for GPT-6 Astra Pro (batch), saving $10.5 (60% lower).
- Kimi K3.1 Pro is $10.5 cheaper on the standard workload (60% lower).
- Kimi K3.1 Pro is $3 cheaper per 1M input tokens (60% lower; 2.5x difference).
- Kimi K3.1 Pro is $15 cheaper per 1M output tokens (60% lower; 2.5x difference).
- GPT-6 Astra Pro (batch) has 1.42K more context (1x larger).
| Feature | NewKimi K3.1 Pro (MoonshotAI) | GPT-6 Astra Pro (batch) (OpenAI) |
|---|---|---|
| Input Price prompt tokens per 1M | $2 | $5 |
| Completion Price per 1M tokens | $10 | $25 |
| Sample Workload Cost 1M input + 500K output | $7 | $17.5 |
| Context Window | 1.05M | 1.05M |
| Release Date |
Use-Case Decision Matrix
| Use case | Better pick | Why |
|---|---|---|
| Budget-constrained production | Kimi K3.1 Pro | On the standard 1M input plus 500K output workload, Kimi K3.1 Pro is estimated at $7 vs $17.5 for GPT-6 Astra Pro (batch), saving $10.5 (60% lower). |
| High-volume input processing | Kimi K3.1 Pro | Lower prompt-token price matters most when prompts, retrieved passages, or documents dominate the bill. |
| Long responses and chatbots | Kimi K3.1 Pro | Lower output-token price matters most when assistants generate many completion tokens. |
| RAG or long-document work | GPT-6 Astra Pro (batch) | A larger context window leaves more room for retrieved passages, conversation history, or source files. |
Related Alternatives
- Kimi K2.7 Code (free) can replace Kimi K3.1 Pro when lower sample workload cost matters most: $0.
- Kimi K2.6 (free) can replace Kimi K3.1 Pro when lower sample workload cost matters most: $0.
- Kimi K2 0711 can replace Kimi K3.1 Pro when lower sample workload cost matters most: $1.72.
- Kimi K2.5 can replace Kimi K3.1 Pro when lower sample workload cost matters most: $1.75.
- Grok 4.20 Multi-Agent offers 2M context with $2.5 sample workload cost.
- Grok 4.20 offers 2M context with $2.5 sample workload cost.
- Llama 4 Scout offers 1.31M context with $0.25 sample workload cost.
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