Solar Pro 4 is $9.97 cheaper per 1M input tokens (99.7% lower; 333.3x difference).
API cost decision in 10 seconds
Solar Pro 4 vs Claude Fable 5
Pick Solar Pro 4 for lower cost; pick Claude Fable 5 only if the larger context window matters more.
Budget verdict
Pick Solar Pro 4 for lower cost; pick Claude Fable 5 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 $35 for Claude Fable 5, saving $34.91 (99.7% lower).
Claude Fable 5 has more context, but Solar Pro 4 saves $34.91 on the standard workload. At 10x that traffic, the same price gap is about $349.1. 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 | Claude Fable 5 |
|---|---|---|---|---|
| Input-heavy / RAG | 5M input + 500K output | Solar Pro 4 | $0.21 | $75 |
| Balanced workload | 1M input + 1M output | Solar Pro 4 | $0.15 | $60 |
| Output-heavy chatbot | 1M input + 5M output | Solar Pro 4 | $0.63 | $260 |
Solar Pro 4 is $49.88 cheaper per 1M output tokens (99.8% lower; 416.7x difference).
Claude Fable 5 has 475.71K more context (1.91x larger).
Solar Pro 4 is $34.91 cheaper on the standard workload (99.7% 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; Claude Fable 5 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 $35 for Claude Fable 5.
Choose Solar Pro 4 when you care most about lower input-token price, and lower output-token price.
Choose Claude Fable 5 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 $35 for Claude Fable 5, saving $34.91 (99.7% lower).
- Solar Pro 4 is $34.91 cheaper on the standard workload (99.7% lower).
- Solar Pro 4 is $9.97 cheaper per 1M input tokens (99.7% lower; 333.3x difference).
- Solar Pro 4 is $49.88 cheaper per 1M output tokens (99.8% lower; 416.7x difference).
- Claude Fable 5 has 475.71K more context (1.91x larger).
| Feature | Solar Pro 4 (Upstage) | Claude Fable 5 (Anthropic) |
|---|---|---|
| Input Price prompt tokens per 1M | $0.03 | $10 |
| Completion Price per 1M tokens | $0.12 | $50 |
| Sample Workload Cost 1M input + 500K output | $0.09 | $35 |
| Context Window | 524.29K | 1M |
| 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 $35 for Claude Fable 5, saving $34.91 (99.7% 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 | Claude Fable 5 | A larger context window leaves more room for retrieved passages, conversation history, or source files. |
Related Alternatives
- Claude 3 Haiku can replace Claude Fable 5 when lower sample workload cost matters most: $0.88.
- Claude Haiku 4.5 (batch) can replace Claude Fable 5 when lower sample workload cost matters most: $1.75.
- Claude 3.5 Haiku can replace Claude Fable 5 when lower sample workload cost matters most: $2.8.
- Claude Sonnet 5 (batch) can replace Claude Fable 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
Review low-cost models sorted by a standard 1M input plus 500K output workload.
Open cheapest modelsLarger context alternatives
Find models with larger context windows for RAG, long documents, and codebase review.
Open largest context modelsProvider catalogs
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Open provider hubsUpstage catalog
Review all tracked Upstage models before deciding whether this matchup is the right shortlist.
Open Upstage modelsAnthropic catalog
Check other Anthropic models with comparable pricing, context, or release timing.
Open Anthropic modelsSolar Pro 4 is Upstage's cost-efficient large language model, featuring a 524K context window. It is built for long-horizon tasks and agentic workflows, with strong capabilities in office productivity, document-intensive...
Claude Fable 5 is a Mythos-class model from Anthropic, built for autonomous knowledge work and coding. It supports text, image, and file inputs with text output, with reasoning support and...