Claude Haiku 5.5 vs GPT-6 Luna
Claude Haiku 5.5 (2026) and GPT-6 Luna (2026) are frontier-tier reasoning models from Anthropic and OpenAI. Claude Haiku 5.5 ships a 1M-token context window, while GPT-6 Luna ships a 1.05M-token context window. On FrontierCode 1.1 Main, Claude Haiku 5.5 leads by 4 pts. This comparison covers specs, pricing, API access, capabilities, benchmarks, input and output token costs, and production fit for coding and agent workloads.
Pick Claude Haiku 5.5 for coding; token pricing is tied, so keep GPT-6 Luna only for already-validated prompts or route constraints.
Decision scorecard
Local evidence first| Signal | Claude Haiku 5.5 | GPT-6 Luna |
|---|---|---|
| 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 | 1.05M |
| Cheapest output | $0.50/1M tokens | $0.50/1M tokens |
| Provider routes | 6 tracked | 4 tracked |
| Shared benchmarks | FrontierCode 1.1 Main leader | 1 shared |
Decision tradeoffs
- Claude Haiku 5.5 holds a shared-benchmark lead on FrontierCode 1.1 Main, ahead by 4 points.
- Claude Haiku 5.5 has broader tracked provider coverage for fallback and route flexibility.
- Local decision data tags Claude Haiku 5.5 for Coding, RAG, and Agents.
- GPT-6 Luna has the larger context window for long prompts, retrieval packs, or transcript analysis.
- GPT-6 Luna uniquely exposes Code execution in local model data.
- Local decision data tags GPT-6 Luna 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 Haiku 5.5
$205
Cheapest tracked route/tier: Anthropic prompts ≤100,000 tokens
GPT-6 Luna
$205
Cheapest tracked route/tier: OpenAI API
Estimated monthly gap: $0.00. Batch, cache, alternate speed tiers, and negotiated pricing are excluded from this local estimate.
Switch friction
- Provider overlap exists on AWS Bedrock and OpenRouter; start route-level A/B tests there.
- Cheapest tracked output pricing is tied, so migration risk shifts to quality, latency, and provider packaging.
- GPT-6 Luna adds Code execution in local capability data.
- Provider overlap exists on AWS Bedrock and OpenRouter; start route-level A/B tests there.
- Cheapest tracked output pricing is tied, so migration risk shifts to quality, latency, and provider packaging.
- Check replacement coverage for Code execution before moving production traffic.
Specs
| Specification | ||
|---|---|---|
| Released | 2026-10-07 | 2026-09-22 |
| Context window | 1M | 1.05M |
| Parameters | — | — |
| Architecture | Decoder Only | - |
| License | Proprietary | Proprietary |
| Openness | Proprietary | Proprietary |
| Weights | Not released | Not released |
| Code | Unknown | Unknown |
| Commercial use | Commercial use: conditional | Commercial use: conditional |
| Knowledge cutoff | 2026-06 | 2026-05 |
Pricing and availability
| Pricing attribute | Claude Haiku 5.5 | GPT-6 Luna |
|---|---|---|
| Input price |
| $0.10/1M tokens |
| Output price |
| $0.50/1M tokens |
| Providers |
Capabilities
| Capability | Claude Haiku 5.5 | GPT-6 Luna |
|---|---|---|
| Vision | Yes | Yes |
| Multimodal | Yes | Yes |
| Reasoning | Yes | Yes |
| JSON / Tool use | Yes | Yes |
| Structured outputs | Yes | Yes |
| Code execution | No | Yes |
| IDE integration | No | No |
| Computer use | No | No |
| Parallel agents | No | No |
Benchmarks
| Benchmark | Claude Haiku 5.5 | GPT-6 Luna |
|---|---|---|
| FrontierCode 1.1 Main | 46.4 | 42.4 |
Deep dive
On shared benchmark coverage, FrontierCode 1.1 Main has Claude Haiku 5.5 at 46.4 and GPT-6 Luna at 42.4, with Claude Haiku 5.5 ahead by 4 points. The largest visible gap is 4 points on FrontierCode 1.1 Main, 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: GPT-6 Luna. Both models share vision, multimodal input, reasoning mode, and JSON / Tool use, 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 Haiku 5.5 lists tiered pricing: prompts ≤100,000 tokens is $0.10/1M input and $0.50/1M output; prompts >100,000 tokens is $0.50/1M input and $2.50/1M output, while GPT-6 Luna lists $0.10/1M input and $0.50/1M output tokens on the cheapest tracked provider. A 70/30 input-output blend is tied on the cheapest tracked routes. 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 4, so concentration risk also matters.
Choose Claude Haiku 5.5 when vision-heavy evaluation and broader provider choice are central to the workload. Choose GPT-6 Luna when coding workflow support and larger context windows 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 Haiku 5.5 or GPT-6 Luna?
GPT-6 Luna supports 1.05M tokens, while Claude Haiku 5.5 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 Haiku 5.5 or GPT-6 Luna?
Neither is cheaper on tracked token pricing. Both list $0.10/1M input and $0.50/1M output tokens on the cheapest tracked route. Provider discounts, batch pricing, or route-specific tiers can still change the final bill.
Is Claude Haiku 5.5 or GPT-6 Luna open source?
Claude Haiku 5.5 is listed under Proprietary. GPT-6 Luna 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 Haiku 5.5 or GPT-6 Luna?
Both Claude Haiku 5.5 and GPT-6 Luna 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 Haiku 5.5 or GPT-6 Luna?
Both Claude Haiku 5.5 and GPT-6 Luna 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 Haiku 5.5 and GPT-6 Luna?
Claude Haiku 5.5 is available on Anthropic, AWS Bedrock, GCP Vertex AI, Microsoft Foundry, and Vercel AI Gateway. GPT-6 Luna is available on OpenAI API, AWS Bedrock, Azure OpenAI, and OpenRouter. Provider coverage can affect latency, region availability, compliance posture, and fallback options.
Continue comparing
Last reviewed: 2026-10-07. Data sourced from public model cards and provider documentation.