AI model comparison
Claude Haiku 5.5 vs GPT-5.6 Luna
Pricing, context window, benchmarks, and features compared side by side. Or skip the guesswork and send one prompt to both.
Anthropic
Claude Haiku 5.5
Claude Haiku 5.5 is Anthropic's small, fast model for high-volume, cost-sensitive work such as summarization, subagents, and browser use.
- Input / 1M
- $0.10
- Output / 1M
- $0.50
- Context
- 1M
OpenAI
GPT-5.6 Luna
GPT-5.6 Luna is a fast, cost-efficient model in OpenAI's GPT-5.6 series.
- Input / 1M
- $0.20
- Output / 1M
- $1.20
- Context
- 1.05M
At a glance
Quick verdict
How the two models stack up on the things people ask about most.
Lower price
Claude Haiku 5.5
2.2x cheaper for a typical chat
Higher intelligence score
Claude Haiku 5.5
43.4 vs 37.3 on Artificial Analysis
Larger context window
GPT-5.6 Luna
1.05M vs 1M tokens
Newer release
Claude Haiku 5.5
Released October 7, 2026
Benchmarks
Benchmark scores
Independent scores from Artificial Analysis. Higher is better.
Intelligence index
Claude Haiku 5.543.4GPT-5.6 Luna37.3Coding index
Claude Haiku 5.5Not availableGPT-5.6 Luna71.4Agentic index
Claude Haiku 5.5Not availableGPT-5.6 Luna42.1Pricing
Claude Haiku 5.5 vs GPT-5.6 Luna API pricing
Per-token API rates. Cheaper option highlighted.
| Metric | Claude Haiku 5.5 | GPT-5.6 Luna |
|---|---|---|
| Input tokensPer 1M tokens | $0.10 | $0.20 |
| Output tokensPer 1M tokens | $0.50 | $1.20 |
| Cached input (read)Per 1M tokens | $0.01 | $0.02 |
| Cache writePer 1M tokens | $0.13 | $0.25 |
| Long-context pricingPer 1M tokens, for very long prompts | $0.50 in / $2.50 out above 100K | $0.40 in / $1.80 out above 272K |
| Web searchPer request | $0.01 | $0.01 |
What it costs in practice
Estimated cost per 1,000 requests at standard rates. Coding and long-document figures also show the cost when the input is already cached.
Chat message
2K in, 500 out
Claude Haiku 5.5$0.45GPT-5.6 Luna$1Coding task
30K in, 4K out
Claude Haiku 5.5$5$2.30 cachedGPT-5.6 Luna$10.80$5.40 cachedLong document summary
150K in, 2K out
Claude Haiku 5.5$16$2.50 cachedGPT-5.6 Luna$32.40$5.40 cachedSpecs
Context window and capabilities
How much each model can read, how much it can write, and what it accepts as input.
| Metric | Claude Haiku 5.5 | GPT-5.6 Luna |
|---|---|---|
| Context window | 1M tokens | 1.05M tokens |
| Max output | 128K tokens | 128K tokens |
| Input types | File, Image, Text | File, Image, Text |
| Output types | Text | Text |
| Reasoning effort levels | Max, Extra high, High, Medium, Low | Max, Extra high, High, Medium, Low, None |
| Default reasoning effort | Medium | Medium |
| Release date | October 7, 2026 | July 9, 2026 |
Features
Supported features
API features available for each model.
| Metric | Claude Haiku 5.5 | GPT-5.6 Luna |
|---|---|---|
| Tool calling | Supported | Supported |
| Structured outputs | Supported | Supported |
| JSON mode | Supported | Supported |
| Reasoning | Supported | Supported |
| Temperature | Not supported | Not supported |
| Stop sequences | Supported | Not supported |
| Deterministic seed | Not supported | Supported |
| Verbosity control | Supported | Supported |
Keep exploring
More on these models
Other head-to-heads, the full model page, and the alternatives list for each model.
Claude Haiku 5.5View full model details- Claude Haiku 5.5 vs MiMo-V2.6-Pro
- Claude Haiku 5.5 vs GLM 5.3
- Claude Haiku 5.5 vs Kimi K3
- Claude Haiku 5.5 vs GLM 5.3 Flash
- Claude Haiku 5.5 vs Gemini 3.8 Flash
- Claude Haiku 5.5 vs DeepSeek V4.1 Flash
- Claude Haiku 5.5 vs MiMo-V2.6-Flash
- Claude Haiku 5.5 vs GPT-6 Luna
- Claude Haiku 5.5 vs DeepSeek V4 Flash 0731
- Claude Haiku 5.5 vs GPT-6 Luna Pro
GPT-5.6 LunaView full model details- GPT-5.6 Luna vs DeepSeek V4.1 Flash
- GPT-5.6 Luna vs GLM 5.3 Flash
- GPT-5.6 Luna vs MiMo-V2.6-Flash
- GPT-5.6 Luna vs Hy4 preview
- GPT-5.6 Luna vs GPT-6 Luna
- GPT-5.6 Luna vs DeepSeek V4 Flash 0731
- GPT-5.6 Luna vs Gemini 3.8 Flash
- GPT-5.6 Luna vs DeepSeek V4 Pro 0813
- GPT-5.6 Luna vs GPT-6 Luna Pro
- GPT-5.6 Luna vs Qwen3.8 27B
- GPT-5.6 Luna vs Gemini 3.7 Flash
- GPT-5.6 Luna vs Muse Spark 1.2
- GPT-5.6 Luna vs GPT-5.5
- GPT-5.6 Luna vs DeepSeek V4 Flash Vision Exp
- GPT-5.6 Luna vs Muse Spark 1.1
- GPT-5.6 Luna vs GLM 5.3 FlashX
- GPT-5.6 Luna vs GPT-5.6 Luna Pro
Our take
Claude Haiku 5.5 is 2.2x cheaper for a typical chat. Claude Haiku 5.5 scores higher on the Artificial Analysis Intelligence Index (43.4 vs 37.3). GPT-5.6 Luna has the larger context window (1.05M vs 1M tokens). The right pick depends on your workload, so the quickest way to settle it is to send the same prompt to both and compare.
FAQ
Frequently asked questions
Is Claude Haiku 5.5 or GPT-5.6 Luna cheaper?
Claude Haiku 5.5 is cheaper for a typical chat (2K input tokens and 500 output tokens). Claude Haiku 5.5 costs $0.10 per 1M input tokens and $0.50 per 1M output tokens, while GPT-5.6 Luna costs $0.20 per 1M input tokens and $1.20 per 1M output tokens.
Which has a bigger context window, Claude Haiku 5.5 or GPT-5.6 Luna?
GPT-5.6 Luna supports up to 1.05M tokens of context, compared with 1M for Claude Haiku 5.5.
Is Claude Haiku 5.5 smarter than GPT-5.6 Luna?
On the Artificial Analysis Intelligence Index, Claude Haiku 5.5 scores 43.4 and GPT-5.6 Luna scores 37.3, putting Claude Haiku 5.5 ahead. Benchmarks don't capture everything, so the best test is running your own prompts through both.
Can I use Claude Haiku 5.5 and GPT-5.6 Luna at the same time?
Yes. Shortcut Chat sends one prompt to multiple models at once, so you can see Claude Haiku 5.5 and GPT-5.6 Luna answer side by side and keep the better response.
Why choose? Ask both.
Send one prompt to Claude Haiku 5.5 and GPT-5.6 Luna at the same time. Compare the answers side by side and keep the best one.