Ox Alpha is free for input tokens while GPT-5.6 Terra Pro costs $2 per 1M tokens.
API cost decision in 10 seconds
New🔥Ox Alpha vs GPT-5.6 Terra Pro
Pick Ox Alpha for lower cost; pick GPT-5.6 Terra Pro 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 Ox Alpha for lower cost; pick GPT-5.6 Terra Pro only if the larger context window matters more.
On the standard 1M input plus 500K output workload, Ox Alpha is estimated at $0 vs $8 for GPT-5.6 Terra Pro, saving $8 (100% lower).
Cost-first pickOx Alpha
Context-first pickGPT-5.6 Terra Pro
Sample savings$8100%
10x traffic gap$80
GPT-5.6 Terra Pro has more context, but Ox Alpha saves $8 on the standard workload. At 10x that traffic, the same price gap is about $80. Use the calculator below to replace the sample workload with your own token volume.
Cost sensitivity
Workload Sensitivity
Ox Alpha stays cheaper across input-heavy, balanced, and output-heavy sample workloads.
| Workload shape | Token mix | Better pick | Ox Alpha | GPT-5.6 Terra Pro |
|---|---|---|---|---|
| Input-heavy / RAG | 5M input + 500K output | Ox Alpha | $0 | $16 |
| Balanced workload | 1M input + 1M output | Ox Alpha | $0 | $14 |
| Output-heavy chatbot | 1M input + 5M output | Ox Alpha | $0 | $62 |
Ox Alpha is free for output tokens while GPT-5.6 Terra Pro costs $12 per 1M tokens.
GPT-5.6 Terra Pro has 1.42K more context (1x larger).
Ox Alpha is free for the standard workload while the other model is estimated at $8.
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
Ox Alpha has the lower input price; Ox Alpha has the lower output price; GPT-5.6 Terra Pro offers the larger context window. For the 1M input plus 500K output sample, Ox Alpha is cheaper for the standard workload.
For a 1M input token plus 500K output token workload, the estimated API cost is $0 for Ox Alpha and $8 for GPT-5.6 Terra Pro.
Choose Ox Alpha when you care most about lower input-token price, and lower output-token price.
Choose GPT-5.6 Terra Pro when you care most about larger context window.
- On the standard 1M input plus 500K output workload, Ox Alpha is estimated at $0 vs $8 for GPT-5.6 Terra Pro, saving $8 (100% lower).
- Ox Alpha is free for the standard workload while the other model is estimated at $8.
- Ox Alpha is free for input tokens while GPT-5.6 Terra Pro costs $2 per 1M tokens.
- Ox Alpha is free for output tokens while GPT-5.6 Terra Pro costs $12 per 1M tokens.
- GPT-5.6 Terra Pro has 1.42K more context (1x larger).
| Feature | New🔥Ox Alpha (stealth) | GPT-5.6 Terra Pro (OpenAI) |
|---|---|---|
| Input Price prompt tokens per 1M | $0 | $2 |
| Completion Price per 1M tokens | $0 | $12 |
| Sample Workload Cost 1M input + 500K output | $0 | $8 |
| Context Window | 1.05M | 1.05M |
| Release Date | ||
| Popularity | #4 |
Use-Case Decision Matrix
| Use case | Better pick | Why |
|---|---|---|
| Budget-constrained production | Ox Alpha | On the standard 1M input plus 500K output workload, Ox Alpha is estimated at $0 vs $8 for GPT-5.6 Terra Pro, saving $8 (100% lower). |
| High-volume input processing | Ox Alpha | Lower prompt-token price matters most when prompts, retrieved passages, or documents dominate the bill. |
| Long responses and chatbots | Ox Alpha | Lower output-token price matters most when assistants generate many completion tokens. |
| RAG or long-document work | GPT-5.6 Terra Pro | A larger context window leaves more room for retrieved passages, conversation history, or source files. |
Related Alternatives
- gpt-oss-120b (free) can replace GPT-5.6 Terra Pro when lower sample workload cost matters most: $0.
- gpt-oss-20b (free) can replace GPT-5.6 Terra Pro when lower sample workload cost matters most: $0.
- gpt-oss-20b can replace GPT-5.6 Terra Pro when lower sample workload cost matters most: $0.1.
- gpt-oss-120b can replace GPT-5.6 Terra Pro when lower sample workload cost matters most: $0.12.
- 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.
- DeepSeek V4 Flash 0731 offers 1.31M context with $0.17 sample workload cost.
- DeepSeek V4 Flash Latest offers 1.31M context with $0.11 sample workload cost.
- DeepSeek V4 Flash 0731 · DeepSeek · #1
- MiMo-V2.5 · Xiaomi · #2
- Hy3 · Tencent · #3
- DeepSeek V4 Flash 0423 · DeepSeek · #5
Cheaper alternatives
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Open OpenAI modelsOx Alpha is a reasoning model designed for coding, sustained agentic work, and production workloads. It is suited for long-horizon software engineering, complex reasoning, and workflows that combine text with...
GPT-5.6 Terra Pro is the same underlying model as [GPT-5.6 Terra](https://openrouter.ai/openai/gpt-5.6-terra), served with `reasoning.mode` set to `pro` for higher-quality responses on complex tasks. Learn more in OpenAI's docs: https://developers.openai.com/api/docs/guides/reasoning#reasoning-mode