Laguna XS 2.1 is $0.14 cheaper per 1M input tokens (70% lower; 3.33x difference).
API cost decision in 10 seconds
GPT-5.6 Luna Pro vs Laguna XS 2.1
Pick Laguna XS 2.1 for lower cost; pick GPT-5.6 Luna Pro only if the larger context window matters more.
Page updated:
Data confirmed:
Prices normalized to USD per 1M tokens
Sample workload: 1M input + 500K output
Budget verdict
Pick Laguna XS 2.1 for lower cost; pick GPT-5.6 Luna Pro only if the larger context window matters more.
On the standard 1M input plus 500K output workload, Laguna XS 2.1 is estimated at $0.12 vs $0.8 for GPT-5.6 Luna Pro, saving $0.68 (85% lower).
Cost-first pickLaguna XS 2.1
Context-first pickGPT-5.6 Luna Pro
Sample savings$0.6885%
10x traffic gap$6.8
GPT-5.6 Luna Pro has more context, but Laguna XS 2.1 saves $0.68 on the standard workload. At 10x that traffic, the same price gap is about $6.8. Use the calculator below to replace the sample workload with your own token volume.
Cost sensitivity
Workload Sensitivity
Laguna XS 2.1 stays cheaper across input-heavy, balanced, and output-heavy sample workloads.
| Workload shape | Token mix | Better pick | GPT-5.6 Luna Pro | Laguna XS 2.1 |
|---|---|---|---|---|
| Input-heavy / RAG | 5M input + 500K output | Laguna XS 2.1 | $1.6 | $0.36 |
| Balanced workload | 1M input + 1M output | Laguna XS 2.1 | $1.4 | $0.18 |
| Output-heavy chatbot | 1M input + 5M output | Laguna XS 2.1 | $6.2 | $0.66 |
Laguna XS 2.1 is $1.08 cheaper per 1M output tokens (90% lower; 10x difference).
GPT-5.6 Luna Pro has 787.86K more context (4.01x larger).
Laguna XS 2.1 is $0.68 cheaper on the standard workload (85% 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
Laguna XS 2.1 has the lower input price; Laguna XS 2.1 has the lower output price; GPT-5.6 Luna Pro offers the larger context window. For the 1M input plus 500K output sample, Laguna XS 2.1 is cheaper for the standard workload.
For a 1M input token plus 500K output token workload, the estimated API cost is $0.8 for GPT-5.6 Luna Pro and $0.12 for Laguna XS 2.1.
Choose GPT-5.6 Luna Pro when you care most about larger context window.
Choose Laguna XS 2.1 when you care most about lower input-token price, and lower output-token price.
- On the standard 1M input plus 500K output workload, Laguna XS 2.1 is estimated at $0.12 vs $0.8 for GPT-5.6 Luna Pro, saving $0.68 (85% lower).
- Laguna XS 2.1 is $0.68 cheaper on the standard workload (85% lower).
- Laguna XS 2.1 is $0.14 cheaper per 1M input tokens (70% lower; 3.33x difference).
- Laguna XS 2.1 is $1.08 cheaper per 1M output tokens (90% lower; 10x difference).
- GPT-5.6 Luna Pro has 787.86K more context (4.01x larger).
| Feature | GPT-5.6 Luna Pro (OpenAI) | Laguna XS 2.1 (Poolside) |
|---|---|---|
| Input Price prompt tokens per 1M | $0.2 | $0.06 |
| Completion Price per 1M tokens | $1.2 | $0.12 |
| Sample Workload Cost 1M input + 500K output | $0.8 | $0.12 |
| Context Window | 1.05M | 262.14K |
| Release Date |
Use-Case Decision Matrix
| Use case | Better pick | Why |
|---|---|---|
| Budget-constrained production | Laguna XS 2.1 | On the standard 1M input plus 500K output workload, Laguna XS 2.1 is estimated at $0.12 vs $0.8 for GPT-5.6 Luna Pro, saving $0.68 (85% lower). |
| High-volume input processing | Laguna XS 2.1 | Lower prompt-token price matters most when prompts, retrieved passages, or documents dominate the bill. |
| Long responses and chatbots | Laguna XS 2.1 | Lower output-token price matters most when assistants generate many completion tokens. |
| RAG or long-document work | GPT-5.6 Luna Pro | 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 Luna Pro when lower sample workload cost matters most: $0.
- gpt-oss-20b (free) can replace GPT-5.6 Luna Pro when lower sample workload cost matters most: $0.
- gpt-oss-20b can replace GPT-5.6 Luna Pro when lower sample workload cost matters most: $0.1.
- gpt-oss-120b can replace GPT-5.6 Luna Pro when lower sample workload cost matters most: $0.12.
- 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.
- DeepSeek V4 Flash 0731 · DeepSeek · #1
- MiMo-V2.5 · Xiaomi · #2
- Hy3 · Tencent · #3
- Ox Alpha · stealth · #4
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Open Poolside modelsGPT-5.6 Luna Pro is the same underlying model as [GPT-5.6 Luna](https://openrouter.ai/openai/gpt-5.6-luna), served with `reasoning.mode` set to `pro` for higher-quality responses on complex tasks. Learn more in OpenAI's docs: https://developers.openai.com/api/docs/guides/reasoning#reasoning-mode
Laguna XS 2.1 is the latest coding agent model in the 33B-A3B category from [Poolside](https://poolside.ai/) and a step forward from their Laguna XS.2 model (released in April 2026). It combines...