Mercury 2 is $0.02 cheaper per 1M input tokens (7.4% lower; 1.08x difference).
API cost decision in 10 seconds
DeepSeek V3.1 Terminus vs Mercury 2
Pick Mercury 2 for lower cost; pick DeepSeek V3.1 Terminus 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 Mercury 2 for lower cost; pick DeepSeek V3.1 Terminus only if the larger context window matters more.
On the standard 1M input plus 500K output workload, Mercury 2 is estimated at $0.62 vs $0.74 for DeepSeek V3.1 Terminus, saving $0.12 (16.1% lower).
Cost-first pickMercury 2
Context-first pickDeepSeek V3.1 Terminus
Sample savings$0.1216.1%
10x traffic gap$1.2
DeepSeek V3.1 Terminus has more context, but Mercury 2 saves $0.12 on the standard workload. At 10x that traffic, the same price gap is about $1.2. Use the calculator below to replace the sample workload with your own token volume.
Cost sensitivity
Workload Sensitivity
Mercury 2 stays cheaper across input-heavy, balanced, and output-heavy sample workloads.
| Workload shape | Token mix | Better pick | DeepSeek V3.1 Terminus | Mercury 2 |
|---|---|---|---|---|
| Input-heavy / RAG | 5M input + 500K output | Mercury 2 | $1.83 | $1.62 |
| Balanced workload | 1M input + 1M output | Mercury 2 | $1.22 | $1 |
| Output-heavy chatbot | 1M input + 5M output | Mercury 2 | $5.02 | $4 |
Mercury 2 is $0.2 cheaper per 1M output tokens (21.1% lower; 1.27x difference).
DeepSeek V3.1 Terminus has 35.84K more context (1.28x larger).
Mercury 2 is $0.12 cheaper on the standard workload (16.1% 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
Mercury 2 has the lower input price; Mercury 2 has the lower output price; DeepSeek V3.1 Terminus offers the larger context window. For the 1M input plus 500K output sample, Mercury 2 is cheaper for the standard workload.
For a 1M input token plus 500K output token workload, the estimated API cost is $0.74 for DeepSeek V3.1 Terminus and $0.62 for Mercury 2.
Choose DeepSeek V3.1 Terminus when you care most about larger context window.
Choose Mercury 2 when you care most about lower input-token price, and lower output-token price.
- On the standard 1M input plus 500K output workload, Mercury 2 is estimated at $0.62 vs $0.74 for DeepSeek V3.1 Terminus, saving $0.12 (16.1% lower).
- Mercury 2 is $0.12 cheaper on the standard workload (16.1% lower).
- Mercury 2 is $0.02 cheaper per 1M input tokens (7.4% lower; 1.08x difference).
- Mercury 2 is $0.2 cheaper per 1M output tokens (21.1% lower; 1.27x difference).
- DeepSeek V3.1 Terminus has 35.84K more context (1.28x larger).
| Feature | DeepSeek V3.1 Terminus (DeepSeek) | Mercury 2 (Inception) |
|---|---|---|
| Input Price prompt tokens per 1M | $0.27 | $0.25 |
| Completion Price per 1M tokens | $0.95 | $0.75 |
| Sample Workload Cost 1M input + 500K output | $0.74 | $0.62 |
| Context Window | 163.84K | 128K |
| Release Date | ||
| Popularity | #82 | #136 |
Use-Case Decision Matrix
| Use case | Better pick | Why |
|---|---|---|
| Budget-constrained production | Mercury 2 | On the standard 1M input plus 500K output workload, Mercury 2 is estimated at $0.62 vs $0.74 for DeepSeek V3.1 Terminus, saving $0.12 (16.1% lower). |
| High-volume input processing | Mercury 2 | Lower prompt-token price matters most when prompts, retrieved passages, or documents dominate the bill. |
| Long responses and chatbots | Mercury 2 | Lower output-token price matters most when assistants generate many completion tokens. |
| RAG or long-document work | DeepSeek V3.1 Terminus | A larger context window leaves more room for retrieved passages, conversation history, or source files. |
Related Alternatives
- DeepSeek V4 Flash (free) can replace DeepSeek V3.1 Terminus when lower sample workload cost matters most: $0.
- DeepSeek V4 Flash can replace DeepSeek V3.1 Terminus when lower sample workload cost matters most: $0.2.
- R1 Distill Qwen 32B can replace DeepSeek V3.1 Terminus when lower sample workload cost matters most: $0.43.
- DeepSeek V3.2 can replace DeepSeek V3.1 Terminus when lower sample workload cost matters most: $0.44.
- Llama 4 Scout offers 10M context with $0.23 sample workload cost.
- Owl Alpha offers 1.05M context with $0 sample workload cost.
- DeepSeek V4 Flash offers 1.05M context with $0.2 sample workload cost.
- MiMo-V2.5 offers 1.05M context with $0.28 sample workload cost.
- Hy3 preview · Tencent · #1
- DeepSeek V4 Flash · DeepSeek · #2
- MiMo-V2.5 · Xiaomi · #3
- Claude Sonnet 4.6 · Anthropic · #4
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