Claude Sonnet 5 vs Fugu Ultra
| Signal | Claude Sonnet 5 | Delta | Fugu Ultra |
|---|---|---|---|
Capabilities | 100 | -- | |
Pricing | 90 | +20 | |
Context window size | 95 | -- | |
Recency | 100 | -- | |
Output Capacity | 85 | -- | |
| Overall Result | 1 wins | of 5 | 0 wins |
Score History
85.2
current score
Claude Sonnet 5
right now
40
current score
Claude Sonnet 5
Anthropic
Fugu Ultra
sakana
Claude Sonnet 5 saves you $1300.00/month
That's $15600.00/year compared to Fugu Ultra at your current usage level of 100K calls/month.
| Metric | Claude Sonnet 5 | Fugu Ultra | Winner |
|---|---|---|---|
| Overall Score | 85 | 40 | Claude Sonnet 5 |
| Rank | #65 | #265 | Claude Sonnet 5 |
| Quality Rank | #65 | #265 | Claude Sonnet 5 |
| Adoption Rank | #65 | #265 | Claude Sonnet 5 |
| Parameters | -- | -- | -- |
| Context Window | 1000K | 1000K | -- |
| Pricing | $2.00/$10.00/M | $5.00/$30.00/M | -- |
| Signal Scores | |||
| Capabilities | 100 | 100 | Claude Sonnet 5 |
| Pricing | 90 | 70 | Claude Sonnet 5 |
| Context window size | 95 | 95 | Claude Sonnet 5 |
| Recency | 100 | 100 | Claude Sonnet 5 |
| Output Capacity | 85 | 85 | Claude Sonnet 5 |
Our score (0-100) is driven by benchmark performance (90%) from Arena Elo ratings, MMLU, GPQA, HumanEval, SWE-bench, and 15+ standardized evaluations. Capabilities and context window serve as tiebreakers (10%). Learn more about our methodology.
Scores 85/100 (rank #65), placing it in the top 78% of all 290 models tracked.
Scores 40/100 (rank #265), placing it in the top 9% of all 290 models tracked.
Claude Sonnet 5 has a 45-point advantage, which typically translates to noticeably stronger performance on complex reasoning, code generation, and multi-step tasks.
Choose Claude Sonnet 5 when you need:
- High-volume production workloads where API costs must be minimized
- Step-by-step reasoning and chain-of-thought problem solving
Choose Fugu Ultra when you need:
- Step-by-step reasoning and chain-of-thought problem solving
Claude Sonnet 5 offers 66% better value per quality point. At 1M tokens/day, you'd spend $180.00/month with Claude Sonnet 5 vs $525.00/month with Fugu Ultra - a $345.00 monthly difference.
Both models have comparable response speeds. For most applications, the latency difference is negligible.
When latency matters most: Interactive chatbots, IDE code completion, real-time translation, and user-facing applications where response time directly impacts experience. For batch processing, background summarization, or offline analysis, latency is less critical.
Code generation & review
Based on overall model capabilities and architecture for coding tasks like generating functions, debugging, and refactoring
Customer support chatbot
Suitable for user-facing chat with competitive response times. Claude Sonnet 5 also offers lower per-token costs for high-volume support
Long document analysis
Larger context window (1000K tokens) can process longer documents, contracts, and research papers in a single pass
Batch data extraction
Lower output pricing ($10.00/M) reduces costs when processing thousands of records daily
Creative writing & content
Higher overall composite score (85/100) correlates with better nuance, coherence, and style in long-form content
Image understanding & OCR
Supports vision input - can analyze screenshots, diagrams, photos, and scanned documents directly
Claude Sonnet 5 clearly outperforms Fugu Ultra with a significant 45.2-point lead. For most general use cases, Claude Sonnet 5 is the stronger choice. However, Fugu Ultra may still excel in niche scenarios.
By Use Case
Best for Quality
Claude Sonnet 5
Marginally better benchmark scores; both are excellent
Best for Cost
Claude Sonnet 5
66% lower pricing; better value at scale
Best for Reliability
Claude Sonnet 5
Higher uptime and faster response speeds
Best for Prototyping
Claude Sonnet 5
Stronger community support and better developer experience
Best for Production
Claude Sonnet 5
Wider enterprise adoption and proven at scale
by Anthropic
- Choose for Quality - Marginally better benchmark scores; both are excellent
- Choose for Cost - 66% lower pricing; better value at scale
- Choose for Reliability - Higher uptime and faster response speeds
- Choose for Prototyping - Stronger community support and better developer experience
- Choose for Production - Wider enterprise adoption and proven at scale
| Capability | Claude Sonnet 5 | Fugu Ultra |
|---|---|---|
| Vision (Image Input) | ||
| Function Calling | ||
| Streaming | ||
| JSON Mode | ||
| Reasoning | ||
| Web Search | ||
| Image Output |
Claude Sonnet 5
Anthropic
Fugu Ultra
sakana
Claude Sonnet 5 saves you $29.40/month
That's 65% cheaper than Fugu Ultra at 1,000 tokens/request and 100 requests/day.
Assumes 60% input / 40% output token ratio per request. Actual costs may vary based on your usage pattern.
| Parameter | Claude Sonnet 5 | Fugu Ultra |
|---|---|---|
| Context Window | 1M | 1M |
| Max Output Tokens | 128,000 | 128,000 |
| Open Source | No | No |
| Created | Jun 30, 2026 | Jun 24, 2026 |