SAFugu Ultra v2 Paid vs 
GPT-5.6 Luna Paid
Fugu Ultra v2 vs GPT-5.6 Luna compared — price per token, context window, multimodality, openness and which to choose. Full 2026 breakdown.
Fugu Ultra v2 — full profile › · GPT-5.6 Luna — full profile ›
Prices & specs refreshed from live data · olud.ai
Open-model prices = cheapest provider via OpenRouter; official maker rates may be higher.
$30 /M outputManaged API (no infra to run)
$1.2 /M outputManaged API (no infra to run)
Fugu Ultra v2 vs GPT-5.6 Luna specs
| Spec | Fugu Ultra v2 | GPT-5.6 Luna | Winner |
|---|---|---|---|
| Maker | Sakana AI | OpenAI | – |
| Type | Proprietary | Proprietary | – |
| Context window | 1M tokens | 1.1M tokens | |
| Input price | $5/M | $0.2/M | |
| Output price | $30/M | $1.2/M | |
| Vision / multimodal | Yes | Yes | = Tie |
| Tool / function calling | Yes | Yes | = Tie |
| Self-hostable | No (API only) | No (API only) | – |
| License | Proprietary | Proprietary | – |
Price gap & when to choose each
GPT-5.6 Luna is ~25× cheaper than Fugu Ultra v2 on output tokens ($1.2 vs $30 per M tokens).
- You want frontier performance through a managed API
- You value reliability & ecosystem
- You don't want to manage infrastructure
- You want frontier performance through a managed API
- You need the longer 1.1M context window
- You want the lower output price
- You value reliability & ecosystem
- You don't want to manage infrastructure
Feature comparison
| Capability | Fugu Ultra v2 | GPT-5.6 Luna |
|---|---|---|
| Open weights (downloadable) | ✗ | ✗ |
| Self-hostable | ✗ | ✗ |
| Runs fully offline | ✗ | ✗ |
| Vision / multimodal | ✓ | ✓ |
| Tool / function calling | ✓ | ✓ |
| 1M+ context window | ✓ | ✓ |
Benchmarks: Fugu Ultra v2 vs GPT-5.6 Luna
Independent benchmark scores measured by Artificial Analysis. Higher is better (except latency).
Benchmark data by Artificial Analysis.
How Fugu Ultra v2 and GPT-5.6 Luna score
| Criterion | Fugu Ultra v2 | GPT-5.6 Luna |
|---|---|---|
| Cost-efficiency | 3.0 | 4.5 |
| Context window | 5.0 | 5.0 |
| Openness | 1.5 | 1.5 |
| Self-hosting | 1.0 | 1.0 |
| Multimodality | 5.0 | 5.0 |
Scores come from live data — output price (cost), context length, open vs closed weights (openness & self-hosting) and vision/tool support (multimodality). Raw task quality isn't scored here; it depends on your benchmark — see the verdict.
What each model is
Fugu Ultra v2 Paid
Fugu Ultra v2 is the higher-performance model in Sakana AI's Fugu family. Rather than a single monolithic model, Fugu is a learned multi-agent orchestration system: a language model trained to...
GPT-5.6 Luna Paid
GPT-5.6 Luna is a fast, cost-efficient model in OpenAI's GPT-5.6 series. It is suited for high-volume, latency-sensitive tasks such as chat, classification, and lightweight agentic workflows, providing capable reasoning for...
Frequently asked questions
Fugu Ultra v2 vs GPT-5.6 Luna — which is cheaper?
GPT-5.6 Luna is cheaper on output ($1.2/M vs $30/M).
Which has the larger context window?
GPT-5.6 Luna offers the larger context window (1.1M tokens).
Fugu Ultra v2 vs GPT-5.6 Luna — which should I pick in 2026?
Choose GPT-5.6 Luna for the lower output price ($1.2/M vs $30/M). It also gives you the larger 1.1M context window.
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