Gemini 3.5 Flash (batch) is $1.25 cheaper per 1M input tokens (62.5% lower; 2.67x difference).
API cost decision in 10 seconds
GPT-5.6 Terra vs Gemini 3.5 Flash (batch)
Pick Gemini 3.5 Flash (batch) for lower cost; pick GPT-5.6 Terra 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 Gemini 3.5 Flash (batch) for lower cost; pick GPT-5.6 Terra only if the larger context window matters more.
On the standard 1M input plus 500K output workload, Gemini 3.5 Flash (batch) is estimated at $3 vs $8 for GPT-5.6 Terra, saving $5 (62.5% lower).
Cost-first pickGemini 3.5 Flash (batch)
Context-first pickGPT-5.6 Terra
Sample savings$562.5%
10x traffic gap$50
GPT-5.6 Terra has more context, but Gemini 3.5 Flash (batch) saves $5 on the standard workload. At 10x that traffic, the same price gap is about $50. Use the calculator below to replace the sample workload with your own token volume.
Cost sensitivity
Workload Sensitivity
Gemini 3.5 Flash (batch) stays cheaper across input-heavy, balanced, and output-heavy sample workloads.
| Workload shape | Token mix | Better pick | GPT-5.6 Terra | Gemini 3.5 Flash (batch) |
|---|---|---|---|---|
| Input-heavy / RAG | 5M input + 500K output | Gemini 3.5 Flash (batch) | $16 | $6 |
| Balanced workload | 1M input + 1M output | Gemini 3.5 Flash (batch) | $14 | $5.25 |
| Output-heavy chatbot | 1M input + 5M output | Gemini 3.5 Flash (batch) | $62 | $23.25 |
Gemini 3.5 Flash (batch) is $7.5 cheaper per 1M output tokens (62.5% lower; 2.67x difference).
GPT-5.6 Terra has 1.42K more context (1x larger).
Gemini 3.5 Flash (batch) is $5 cheaper on the standard workload (62.5% 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
Gemini 3.5 Flash (batch) has the lower input price; Gemini 3.5 Flash (batch) has the lower output price; GPT-5.6 Terra offers the larger context window. For the 1M input plus 500K output sample, Gemini 3.5 Flash (batch) is cheaper for the standard workload.
For a 1M input token plus 500K output token workload, the estimated API cost is $8 for GPT-5.6 Terra and $3 for Gemini 3.5 Flash (batch).
Choose GPT-5.6 Terra when you care most about larger context window.
Choose Gemini 3.5 Flash (batch) when you care most about lower input-token price, and lower output-token price.
- On the standard 1M input plus 500K output workload, Gemini 3.5 Flash (batch) is estimated at $3 vs $8 for GPT-5.6 Terra, saving $5 (62.5% lower).
- Gemini 3.5 Flash (batch) is $5 cheaper on the standard workload (62.5% lower).
- Gemini 3.5 Flash (batch) is $1.25 cheaper per 1M input tokens (62.5% lower; 2.67x difference).
- Gemini 3.5 Flash (batch) is $7.5 cheaper per 1M output tokens (62.5% lower; 2.67x difference).
- GPT-5.6 Terra has 1.42K more context (1x larger).
| Feature | GPT-5.6 Terra (OpenAI) | Gemini 3.5 Flash (batch) (Google) |
|---|---|---|
| Input Price prompt tokens per 1M | $2 | $0.75 |
| Completion Price per 1M tokens | $12 | $4.5 |
| Sample Workload Cost 1M input + 500K output | $8 | $3 |
| Context Window | 1.05M | 1.05M |
| Release Date |
Use-Case Decision Matrix
| Use case | Better pick | Why |
|---|---|---|
| Budget-constrained production | Gemini 3.5 Flash (batch) | On the standard 1M input plus 500K output workload, Gemini 3.5 Flash (batch) is estimated at $3 vs $8 for GPT-5.6 Terra, saving $5 (62.5% lower). |
| High-volume input processing | Gemini 3.5 Flash (batch) | Lower prompt-token price matters most when prompts, retrieved passages, or documents dominate the bill. |
| Long responses and chatbots | Gemini 3.5 Flash (batch) | Lower output-token price matters most when assistants generate many completion tokens. |
| RAG or long-document work | GPT-5.6 Terra | 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 when lower sample workload cost matters most: $0.
- gpt-oss-20b (free) can replace GPT-5.6 Terra when lower sample workload cost matters most: $0.
- gpt-oss-20b can replace GPT-5.6 Terra when lower sample workload cost matters most: $0.1.
- gpt-oss-120b can replace GPT-5.6 Terra 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
- Ox Alpha · stealth · #4
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