Claude Opus 4.8 vs Fugu Ultra
Claude Opus 4.8 (2026) and Fugu Ultra (2026) are frontier-tier reasoning models from Anthropic and Sakana AI. Claude Opus 4.8 ships a 1m-token context window, while Fugu Ultra ships a 1m-token context window. On SWE-bench Pro, Fugu Ultra leads by 4.5 pts. This comparison covers specs, pricing, API access, capabilities, benchmarks, input and output token costs, and production fit for coding and agent workloads.
Pick Fugu Ultra for coding; Claude Opus 4.8 is better when coding workflow support matters more.
Decision scorecard
Local evidence first| Signal | Claude Opus 4.8 | Fugu Ultra |
|---|---|---|
| Best for | reasoning-heavy apps, multimodal apps, and tool-calling agents | reasoning-heavy apps, multimodal apps, and tool-calling agents |
| Decision fit | Coding, RAG, and Agents | Coding, RAG, and Agents |
| Context window | 1m | 1m |
| Cheapest output | $25/1M tokens | $30/1M tokens |
| Provider routes | 6 tracked | 2 tracked |
| Shared benchmarks | 4 shared | SWE-bench Pro leader |
Decision tradeoffs
- Claude Opus 4.8 has the lower cheapest tracked output price at $25/1M tokens.
- Claude Opus 4.8 has broader tracked provider coverage for fallback and procurement flexibility.
- Claude Opus 4.8 uniquely exposes Code execution, Computer use, and Parallel agents in local model data.
- Local decision data tags Claude Opus 4.8 for Coding, RAG, and Agents.
- Fugu Ultra holds a shared-benchmark lead on SWE-bench Pro, ahead by 4.5 points.
- Local decision data tags Fugu Ultra for Coding, RAG, and Agents.
Monthly cost at traffic
Estimate token spend from the cheapest tracked input and output route or tier on this page.
Claude Opus 4.8
$10,250
Cheapest tracked route/tier: Anthropic
Fugu Ultra
$11,500
Cheapest tracked route/tier: Sakana AI <=272K tokens
Estimated monthly gap: $1,250. Batch, cache, alternate speed tiers, and negotiated pricing are excluded from this local estimate.
Switch friction
- Provider overlap exists on Vercel AI Gateway; start route-level A/B tests there.
- Fugu Ultra is $5/1M tokens higher on cheapest tracked output pricing, so quality gains need to justify the spend.
- Check replacement coverage for Code execution, Computer use, and Parallel agents before moving production traffic.
- Provider overlap exists on Vercel AI Gateway; start route-level A/B tests there.
- Claude Opus 4.8 is $5/1M tokens lower on cheapest tracked output pricing before cache, batch, or negotiated discounts.
- Claude Opus 4.8 adds Code execution, Computer use, and Parallel agents in local capability data.
Specs
| Specification | ||
|---|---|---|
| Released | 2026-05-28 | 2026-06-22 |
| Context window | 1m | 1m |
| Parameters | — | — |
| Architecture | Decoder Only | Composition of Experts |
| License | Proprietary | Proprietary |
| Openness | Proprietary | Proprietary |
| Commercial use | Commercial use: conditional | Commercial use: conditional |
| Knowledge cutoff | 2026-01 | - |
Pricing and availability
| Pricing attribute | Claude Opus 4.8 | Fugu Ultra |
|---|---|---|
| Input price | $5/1M tokens |
|
| Output price | $25/1M tokens |
|
| Providers |
Capabilities
| Capability | Claude Opus 4.8 | Fugu Ultra |
|---|---|---|
| Vision | Yes | Yes |
| Multimodal | Yes | Yes |
| Reasoning | Yes | Yes |
| Function calling | Yes | Yes |
| Tool use | Yes | Yes |
| Structured outputs | Yes | Yes |
| Code execution | Yes | No |
| IDE integration | No | No |
| Computer use | Yes | No |
| Parallel agents | Yes | No |
Benchmarks
| Benchmark | Claude Opus 4.8 | Fugu Ultra |
|---|---|---|
| SWE-bench Pro | 69.2 | 73.7 |
| Google-Proof Q&A | 93.6 | 95.5 |
| LiveCodeBench | 88.8 | 93.2 |
| Terminal-Bench 2.1 | 74.6 | 82.1 |
Deep dive
On shared benchmark coverage, SWE-bench Pro has Claude Opus 4.8 at 69.2 and Fugu Ultra at 73.7, with Fugu Ultra ahead by 4.5 points; Google-Proof Q&A has Claude Opus 4.8 at 93.6 and Fugu Ultra at 95.5, with Fugu Ultra ahead by 1.9 points; LiveCodeBench has Claude Opus 4.8 at 88.8 and Fugu Ultra at 93.2, with Fugu Ultra ahead by 4.4 points. The largest visible gap is 4.5 points on SWE-bench Pro, which matters most when that benchmark mirrors your workload. Treat isolated benchmark wins as directional, because provider routing, prompt style, and tool access can move real application results.
The capability footprint differs most on code execution: Claude Opus 4.8. Both models share vision, multimodal input, reasoning mode, and function calling, so the practical split is not just feature count. Use those differences to decide whether the page is about raw model quality, agentic coding support, multimodal ingestion, or predictable structured API behavior.
For cost, Claude Opus 4.8 lists $5/1M input and $25/1M output tokens on the cheapest tracked provider, while Fugu Ultra lists tiered pricing: <=272K tokens is $5/1M input and $30/1M output; >272K tokens is $10/1M input and $45/1M output. A 70/30 input-output blend puts Claude Opus 4.8 lower by about $1.50 per million blended tokens. For tiered rows, this cheapest-track view can understate interactive or fast-lane spend, so compare the tier you will actually use. Availability is 6 providers versus 2, so concentration risk also matters.
Choose Claude Opus 4.8 when coding workflow support and broader provider choice are central to the workload. Choose Fugu Ultra when vision-heavy evaluation are more important. For production, rerun your own prompts through the exact provider, region, and tool stack you plan to ship.
FAQ
Which has a larger context window, Claude Opus 4.8 or Fugu Ultra?
Claude Opus 4.8 supports 1m tokens, while Fugu Ultra supports 1m tokens. That gap matters most for long documents, large codebases, retrieval-heavy agents, and conversations where earlier context must remain visible.
Which is cheaper, Claude Opus 4.8 or Fugu Ultra?
Claude Opus 4.8 lists $5/1M input and $25/1M output tokens on the cheapest tracked provider. Fugu Ultra lists tiered pricing: <=272K tokens is $5/1M input and $30/1M output; >272K tokens is $10/1M input and $45/1M output. Compare the tier you will actually use; cheap async pricing can overstate savings for interactive workflows. Provider discounts or batch pricing can still change the final bill.
Is Claude Opus 4.8 or Fugu Ultra open source?
Claude Opus 4.8 is listed under Proprietary. Fugu Ultra is listed under Proprietary. License labels affect whether you can self-host, redistribute weights, or rely only on hosted APIs, so confirm the upstream license before deployment.
Which is better for vision, Claude Opus 4.8 or Fugu Ultra?
Both Claude Opus 4.8 and Fugu Ultra expose vision. The better choice depends on benchmark fit, context budget, pricing, and whether your provider route exposes the same capability surface. Use this as a quick comparison signal, then confirm the provider-specific limits before committing to production.
Which is better for multimodal input, Claude Opus 4.8 or Fugu Ultra?
Both Claude Opus 4.8 and Fugu Ultra expose multimodal input. The better choice depends on benchmark fit, context budget, pricing, and whether your provider route exposes the same capability surface.
Where can I run Claude Opus 4.8 and Fugu Ultra?
Claude Opus 4.8 is available on Anthropic, AWS Bedrock, GCP Vertex AI, Microsoft Foundry, and OpenRouter. Fugu Ultra is available on Sakana AI and Vercel AI Gateway. Provider coverage can affect latency, region availability, compliance posture, and fallback options.
Continue comparing
Last reviewed: 2026-06-22. Data sourced from public model cards and provider documentation.