Claude Haiku 5.5 and GPT-6 Luna are the lowest-cost tiers in Anthropic's and OpenAI's current line-ups, aimed at high-volume work where per-call cost and latency matter most.
Figures come from Anthropic's Models overview and OpenAI's Models page, both re-read on 2026-11-02.
Key differences at a glance
- Price: from $0.10 / from $0.50 (Haiku) against $0.10 / $0.50 (Luna) per million input/output tokens.
- Context: 1M against 1.05M tokens; both list 128K output.
- Knowledge cutoff: June 2026 against May 18, 2026.
- Anthropic labels Haiku 5.5 'Fastest' in its line-up; OpenAI's page gives no latency label for Luna.
- Both target classification, extraction, routing and other focused, high-volume tasks.
Specification comparison
| Feature | Claude Haiku 5.5 | GPT-6 Luna |
|---|---|---|
| Positioning | High-volume, latency-sensitive tasks | Most efficient; focused, high-volume tasks |
| Price per MTok (in / out) | From $0.10 / From $0.50 | $0.10 / $0.50 |
| Context / max output | 1M / 128K | 1.05M / 128K |
| Latency label | Fastest | Not stated in the cited source |
| Knowledge cutoff | Jun 2026 | May 18, 2026 |
| Input modalities | Text and image | Text and image |
Shaded cells mean the cited sources did not state the value. We do not fill gaps from memory.
Same price point
Both list the same base prices. Anthropic writes Haiku's as starting prices and offers Batch API discounts and cache-read pricing; check OpenAI's pricing page for its batch and caching terms, which are not on the Models page. At this price point, total cost depends heavily on output length and retry rate.
What each vendor emphasises
Anthropic positions Haiku 5.5 for high-volume, latency-sensitive tasks such as classification, extraction and routing, and labels it the fastest current Claude model. OpenAI calls Luna its most efficient model for focused, high-volume tasks. Both accept text and image input.
Evaluate on your own data
Small models can differ sharply on specific formats, languages and edge cases. Build a test set of a few hundred real examples, measure accuracy, latency and cost per correct answer, and include failure handling.
Strengths and limitations
Claude Haiku 5.5
Strengths
- Latency labelled fastest; later cutoff.
Limitations
- Prices stated as 'From'.
GPT-6 Luna
Strengths
- Fixed listed price and slightly larger context.
Limitations
- No latency label on the page.
Verified pricing
Haiku: from $0.10 / $0.50. Luna: $0.10 / $0.50. Prices are per million tokens (MTok) as listed on the cited page on the verification date; they can change.
Which should you choose?
- Lowest latency: Claude Haiku 5.5 — labelled Fastest
- Predictable listed price: GPT-6 Luna — $0.10 / $0.50 stated
Our verdict
Pricing is nearly the same on paper. Run a small evaluation to compare latency and accuracy, which these pages do not measure.
Frequently asked questions
Which is cheaper, Claude Haiku 5.5 or GPT-6 Luna?
Both list $0.10 per million input tokens and $0.50 per million output tokens; Anthropic writes Haiku's as starting prices.
Which is faster?
Anthropic labels Haiku 5.5 the fastest in its line-up; OpenAI does not give Luna a latency label. Only your own measurements can compare them.
Can they handle long documents?
Both list context windows of about one million tokens.
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How this was checked
Specifications compiled on 2026-11-02 from the sources below. The cited sources were re-opened and the key table values re-checked on 2026-11-02.
Both vendor pages re-read on 2026-11-02; prices, limits, descriptions and cutoffs matched.
Disclosure: AYORAHUB did not hands-on test these products or services. Nothing on this page is a lab measurement, benchmark or review score; analysis explains what the cited specifications mean in practice.
- All Anthropic figures come from the single Models overview page; availability on cloud platforms is not stated there.
- OpenAI figures come from the Models listing page; individual model pages may add detail.
Sources
- Models overview — Anthropic Claude Platform Docs (manufacturer/official)
- Models — OpenAI API Docs (manufacturer/official)