Both models report the same input price at $2 per 1M tokens.
API cost decision in 10 seconds
🔥Claude Sonnet 5 vs GPT-5.6 Terra Pro
Pick Claude Sonnet 5 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 Claude Sonnet 5 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, Claude Sonnet 5 is estimated at $7 vs $8 for GPT-5.6 Terra Pro, saving $1 (12.5% lower).
Cost-first pickClaude Sonnet 5
Context-first pickGPT-5.6 Terra Pro
Sample savings$112.5%
10x traffic gap$10
GPT-5.6 Terra Pro has more context, but Claude Sonnet 5 saves $1 on the standard workload. At 10x that traffic, the same price gap is about $10. Use the calculator below to replace the sample workload with your own token volume.
Cost sensitivity
Workload Sensitivity
Claude Sonnet 5 stays cheaper across input-heavy, balanced, and output-heavy sample workloads.
| Workload shape | Token mix | Better pick | Claude Sonnet 5 | GPT-5.6 Terra Pro |
|---|---|---|---|---|
| Input-heavy / RAG | 5M input + 500K output | Claude Sonnet 5 | $15 | $16 |
| Balanced workload | 1M input + 1M output | Claude Sonnet 5 | $12 | $14 |
| Output-heavy chatbot | 1M input + 5M output | Claude Sonnet 5 | $52 | $62 |
Claude Sonnet 5 is $2 cheaper per 1M output tokens (16.7% lower; 1.2x difference).
GPT-5.6 Terra Pro has 50K more context (1.05x larger).
Claude Sonnet 5 is $1 cheaper on the standard workload (12.5% 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
both models tie on input price; Claude Sonnet 5 has the lower output price; GPT-5.6 Terra Pro offers the larger context window. For the 1M input plus 500K output sample, Claude Sonnet 5 is cheaper for the standard workload.
For a 1M input token plus 500K output token workload, the estimated API cost is $7 for Claude Sonnet 5 and $8 for GPT-5.6 Terra Pro.
Choose Claude Sonnet 5 when you care most about 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, Claude Sonnet 5 is estimated at $7 vs $8 for GPT-5.6 Terra Pro, saving $1 (12.5% lower).
- Claude Sonnet 5 is $1 cheaper on the standard workload (12.5% lower).
- Both models report the same input price at $2 per 1M tokens.
- Claude Sonnet 5 is $2 cheaper per 1M output tokens (16.7% lower; 1.2x difference).
- GPT-5.6 Terra Pro has 50K more context (1.05x larger).
| Feature | 🔥Claude Sonnet 5 (Anthropic) | GPT-5.6 Terra Pro (OpenAI) |
|---|---|---|
| Input Price prompt tokens per 1M | $2 | $2 |
| Completion Price per 1M tokens | $10 | $12 |
| Sample Workload Cost 1M input + 500K output | $7 | $8 |
| Context Window | 1M | 1.05M |
| Release Date | ||
| Popularity | #16 |
Use-Case Decision Matrix
| Use case | Better pick | Why |
|---|---|---|
| Budget-constrained production | Claude Sonnet 5 | On the standard 1M input plus 500K output workload, Claude Sonnet 5 is estimated at $7 vs $8 for GPT-5.6 Terra Pro, saving $1 (12.5% lower). |
| High-volume input processing | Tie | Lower prompt-token price matters most when prompts, retrieved passages, or documents dominate the bill. |
| Long responses and chatbots | Claude Sonnet 5 | 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
- Claude 3 Haiku can replace Claude Sonnet 5 when lower sample workload cost matters most: $0.88.
- Claude Haiku 4.5 (batch) can replace Claude Sonnet 5 when lower sample workload cost matters most: $1.75.
- Claude 3.5 Haiku can replace Claude Sonnet 5 when lower sample workload cost matters most: $2.8.
- Claude Sonnet 5 (batch) can replace Claude Sonnet 5 when lower sample workload cost matters most: $3.5.
- 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
- Ox Alpha · stealth · #4
Cheaper alternatives
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Open OpenAI modelsSonnet 5 is Anthropic's most capable Sonnet-class model, with frontier performance across coding, agents, and professional work. It supports adaptive thinking with selectable reasoning effort levels (low, medium, high, max,...
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