Solar Pro 4 is $0.42 cheaper per 1M input tokens (93.3% lower; 15x difference).
API cost decision in 10 seconds
Solar Pro 4 vs Inkling Small
Pick Solar Pro 4 for lower cost; pick Inkling Small 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 Solar Pro 4 for lower cost; pick Inkling Small only if the larger context window matters more.
On the standard 1M input plus 500K output workload, Solar Pro 4 is estimated at $0.09 vs $1.05 for Inkling Small, saving $0.96 (91.4% lower).
Cost-first pickSolar Pro 4
Context-first pickInkling Small
Sample savings$0.9691.4%
10x traffic gap$9.6
Inkling Small has more context, but Solar Pro 4 saves $0.96 on the standard workload. At 10x that traffic, the same price gap is about $9.6. Use the calculator below to replace the sample workload with your own token volume.
Cost sensitivity
Workload Sensitivity
Solar Pro 4 stays cheaper across input-heavy, balanced, and output-heavy sample workloads.
| Workload shape | Token mix | Better pick | Solar Pro 4 | Inkling Small |
|---|---|---|---|---|
| Input-heavy / RAG | 5M input + 500K output | Solar Pro 4 | $0.21 | $2.85 |
| Balanced workload | 1M input + 1M output | Solar Pro 4 | $0.15 | $1.65 |
| Output-heavy chatbot | 1M input + 5M output | Solar Pro 4 | $0.63 | $6.45 |
Solar Pro 4 is $1.08 cheaper per 1M output tokens (90% lower; 10x difference).
Inkling Small has 524.29K more context (2x larger).
Solar Pro 4 is $0.96 cheaper on the standard workload (91.4% 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
Solar Pro 4 has the lower input price; Solar Pro 4 has the lower output price; Inkling Small offers the larger context window. For the 1M input plus 500K output sample, Solar Pro 4 is cheaper for the standard workload.
For a 1M input token plus 500K output token workload, the estimated API cost is $0.09 for Solar Pro 4 and $1.05 for Inkling Small.
Choose Solar Pro 4 when you care most about lower input-token price, and lower output-token price.
Choose Inkling Small when you care most about larger context window.
- On the standard 1M input plus 500K output workload, Solar Pro 4 is estimated at $0.09 vs $1.05 for Inkling Small, saving $0.96 (91.4% lower).
- Solar Pro 4 is $0.96 cheaper on the standard workload (91.4% lower).
- Solar Pro 4 is $0.42 cheaper per 1M input tokens (93.3% lower; 15x difference).
- Solar Pro 4 is $1.08 cheaper per 1M output tokens (90% lower; 10x difference).
- Inkling Small has 524.29K more context (2x larger).
| Feature | Solar Pro 4 (Upstage) | Inkling Small (Thinking Machines) |
|---|---|---|
| Input Price prompt tokens per 1M | $0.03 | $0.45 |
| Completion Price per 1M tokens | $0.12 | $1.2 |
| Sample Workload Cost 1M input + 500K output | $0.09 | $1.05 |
| Context Window | 524.29K | 1.05M |
| Release Date |
Use-Case Decision Matrix
| Use case | Better pick | Why |
|---|---|---|
| Budget-constrained production | Solar Pro 4 | On the standard 1M input plus 500K output workload, Solar Pro 4 is estimated at $0.09 vs $1.05 for Inkling Small, saving $0.96 (91.4% lower). |
| High-volume input processing | Solar Pro 4 | Lower prompt-token price matters most when prompts, retrieved passages, or documents dominate the bill. |
| Long responses and chatbots | Solar Pro 4 | Lower output-token price matters most when assistants generate many completion tokens. |
| RAG or long-document work | Inkling Small | A larger context window leaves more room for retrieved passages, conversation history, or source files. |
Related Alternatives
- Inkling Small (free) can replace Inkling Small when lower sample workload cost matters most: $0.
- Inkling (free) can replace Inkling Small when lower sample workload cost matters most: $0.
- 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.
- Llama 4 Scout offers 1.31M context with $0.25 sample workload cost.
- MiMo-V2.5 offers 1.05M context with $0.28 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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