Sakana Namazu is $0.05 cheaper per 1M input tokens (5% lower; 1.05x difference).
API cost decision in 10 seconds
New🔥Step 5 Preview vs Sakana Namazu
Pick Step 5 Preview when budget and context both matter.
Budget verdict
Pick Step 5 Preview when budget and context both matter.
On the standard 1M input plus 500K output workload, Step 5 Preview is estimated at $2.35 vs $2.95 for Sakana Namazu, saving $0.6 (20.3% lower).
Step 5 Preview is cheaper on the standard workload and also has the larger context window. At 10x that traffic, the same price gap is about $6. Use the calculator below to replace the sample workload with your own token volume.
Cost sensitivity
Workload Sensitivity
Step 5 Preview stays cheaper across input-heavy, balanced, and output-heavy sample workloads.
| Workload shape | Token mix | Better pick | Step 5 Preview | Sakana Namazu |
|---|---|---|---|---|
| Input-heavy / RAG | 5M input + 500K output | Step 5 Preview | $6.35 | $6.75 |
| Balanced workload | 1M input + 1M output | Step 5 Preview | $3.7 | $4.95 |
| Output-heavy chatbot | 1M input + 5M output | Step 5 Preview | $14.5 | $20.95 |
Step 5 Preview is $1.3 cheaper per 1M output tokens (32.5% lower; 1.48x difference).
Step 5 Preview has 737.86K more context (3.81x larger).
Step 5 Preview is $0.6 cheaper on the standard workload (20.3% 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
Sakana Namazu has the lower input price; Step 5 Preview has the lower output price; Step 5 Preview offers the larger context window. For the 1M input plus 500K output sample, Step 5 Preview is cheaper for the standard workload.
For a 1M input token plus 500K output token workload, the estimated API cost is $2.35 for Step 5 Preview and $2.95 for Sakana Namazu.
Choose Step 5 Preview when you care most about lower output-token price, and larger context window.
Choose Sakana Namazu when you care most about lower input-token price.
- On the standard 1M input plus 500K output workload, Step 5 Preview is estimated at $2.35 vs $2.95 for Sakana Namazu, saving $0.6 (20.3% lower).
- Step 5 Preview is $0.6 cheaper on the standard workload (20.3% lower).
- Sakana Namazu is $0.05 cheaper per 1M input tokens (5% lower; 1.05x difference).
- Step 5 Preview is $1.3 cheaper per 1M output tokens (32.5% lower; 1.48x difference).
- Step 5 Preview has 737.86K more context (3.81x larger).
| Feature | New🔥Step 5 Preview (StepFun) | Sakana Namazu (Sakana) |
|---|---|---|
| Input Price prompt tokens per 1M | $1 | $0.95 |
| Completion Price per 1M tokens | $2.7 | $4 |
| Sample Workload Cost 1M input + 500K output | $2.35 | $2.95 |
| Context Window | 1M | 262.14K |
| Release Date | ||
| Popularity | #2 |
Use-Case Decision Matrix
| Use case | Better pick | Why |
|---|---|---|
| Budget-constrained production | Step 5 Preview | On the standard 1M input plus 500K output workload, Step 5 Preview is estimated at $2.35 vs $2.95 for Sakana Namazu, saving $0.6 (20.3% lower). |
| High-volume input processing | Sakana Namazu | Lower prompt-token price matters most when prompts, retrieved passages, or documents dominate the bill. |
| Long responses and chatbots | Step 5 Preview | Lower output-token price matters most when assistants generate many completion tokens. |
| RAG or long-document work | Step 5 Preview | A larger context window leaves more room for retrieved passages, conversation history, or source files. |
Related Alternatives
- Step 3.5 Flash can replace Step 5 Preview when lower sample workload cost matters most: $0.25.
- Step 3.7 Flash can replace Step 5 Preview when lower sample workload cost matters most: $0.77.
- 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.
- Llama 4 Scout offers 1.31M context with $0.47 sample workload cost.
- MiMo-V2.6-Flash offers 1.05M context with $0.28 sample workload cost.
- DeepSeek V4.1 Flash · DeepSeek · #1
- GLM 5.3 Flash · Z.ai · #3
- MiMo-V2.6-Flash · Xiaomi · #4
- Hy4 preview · Tencent · #5
Cheaper alternatives
Review low-cost models sorted by a standard 1M input plus 500K output workload.
Open cheapest modelsLarger context alternatives
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