Aion-2.0 is $0.45 cheaper per 1M input tokens (36% lower; 1.56x difference).
API cost decision in 10 seconds
Aion-2.0 vs GPT-5.1 Chat
Pick Aion-2.0 when budget and context both matter.
Pricing data updated:
Prices normalized to USD per 1M tokens
Sample workload: 1M input + 500K output
Budget verdict
Pick Aion-2.0 when budget and context both matter.
On the standard 1M input plus 500K output workload, Aion-2.0 is estimated at $1.6 vs $6.25 for GPT-5.1 Chat, saving $4.65 (74.4% lower).
Cost-first pickAion-2.0
Context-first pickAion-2.0
Sample savings$4.6574.4%
10x traffic gap$46.5
Aion-2.0 is cheaper on the standard workload and also has the larger context window. At 10x that traffic, the same price gap is about $46.5. Use the calculator below to replace the sample workload with your own token volume.
Cost sensitivity
Workload Sensitivity
Aion-2.0 stays cheaper across input-heavy, balanced, and output-heavy sample workloads.
| Workload shape | Token mix | Better pick | Aion-2.0 | GPT-5.1 Chat |
|---|---|---|---|---|
| Input-heavy / RAG | 5M input + 500K output | Aion-2.0 | $4.8 | $11.25 |
| Balanced workload | 1M input + 1M output | Aion-2.0 | $2.4 | $11.25 |
| Output-heavy chatbot | 1M input + 5M output | Aion-2.0 | $8.8 | $51.25 |
Aion-2.0 is $8.4 cheaper per 1M output tokens (84% lower; 6.25x difference).
Aion-2.0 has 3.07K more context (1.02x larger).
Aion-2.0 is $4.65 cheaper on the standard workload (74.4% 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
Aion-2.0 has the lower input price; Aion-2.0 has the lower output price; Aion-2.0 offers the larger context window. For the 1M input plus 500K output sample, Aion-2.0 is cheaper for the standard workload.
For a 1M input token plus 500K output token workload, the estimated API cost is $1.6 for Aion-2.0 and $6.25 for GPT-5.1 Chat.
Choose Aion-2.0 when you care most about lower input-token price, lower output-token price, and larger context window.
Choose GPT-5.1 Chat when its provider, model quality, latency, or availability is more important than the numeric price/context winner.
- On the standard 1M input plus 500K output workload, Aion-2.0 is estimated at $1.6 vs $6.25 for GPT-5.1 Chat, saving $4.65 (74.4% lower).
- Aion-2.0 is $4.65 cheaper on the standard workload (74.4% lower).
- Aion-2.0 is $0.45 cheaper per 1M input tokens (36% lower; 1.56x difference).
- Aion-2.0 is $8.4 cheaper per 1M output tokens (84% lower; 6.25x difference).
- Aion-2.0 has 3.07K more context (1.02x larger).
| Feature | Aion-2.0 (AionLabs) | GPT-5.1 Chat (OpenAI) |
|---|---|---|
| Input Price prompt tokens per 1M | $0.8 | $1.25 |
| Completion Price per 1M tokens | $1.6 | $10 |
| Sample Workload Cost 1M input + 500K output | $1.6 | $6.25 |
| Context Window | 131.07K | 128K |
| Release Date |
Use-Case Decision Matrix
| Use case | Better pick | Why |
|---|---|---|
| Budget-constrained production | Aion-2.0 | On the standard 1M input plus 500K output workload, Aion-2.0 is estimated at $1.6 vs $6.25 for GPT-5.1 Chat, saving $4.65 (74.4% lower). |
| High-volume input processing | Aion-2.0 | Lower prompt-token price matters most when prompts, retrieved passages, or documents dominate the bill. |
| Long responses and chatbots | Aion-2.0 | Lower output-token price matters most when assistants generate many completion tokens. |
| RAG or long-document work | Aion-2.0 | A larger context window leaves more room for retrieved passages, conversation history, or source files. |
Related Alternatives
- Aion-1.0-Mini can replace Aion-2.0 when lower sample workload cost matters most: $1.4.
- gpt-oss-120b (free) can replace GPT-5.1 Chat when lower sample workload cost matters most: $0.
- gpt-oss-20b (free) can replace GPT-5.1 Chat when lower sample workload cost matters most: $0.
- gpt-oss-20b can replace GPT-5.1 Chat when lower sample workload cost matters most: $0.1.
- Llama 4 Scout offers 10M context with $0.23 sample workload cost.
- Grok 4.20 Multi-Agent offers 2M context with $5 sample workload cost.
- Grok 4.20 offers 2M context with $2.5 sample workload cost.
- Owl Alpha offers 1.05M context with $0 sample workload cost.
- No popular competitor is currently available.
Cheaper alternatives
Review low-cost models sorted by a standard 1M input plus 500K output workload.
Open cheapest modelsLarger context alternatives
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Open provider hubsAionLabs catalog
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