Skip to main content
AI Choice Engine

Model comparison

Claude Haiku 4.5 vs GPT-6 Luna

Anthropic against OpenAI, compared on context, price, and verified benchmark results.

Catalog record checked September 26, 2026Individual provider fields may changeEvidence confidence: High — see receipts below

Anthropic

Claude Haiku 4.5

Budget

vs

OpenAI

GPT-6 Luna

Budget

AI model capability comparison
SpecificationClaude Haiku 4.5GPT-6 Luna
ProviderAnthropicOpenAI
TierBudgetBudget
Context window200KWinner: 1.05M
Max output64KWinner: 128K
Input / 1M tokens$1Winner: $0.10
Output / 1M tokens$5Winner: $0.50
WeightsClosedClosed
ParametersNot disclosedUnverifiedGPT-6 low-cost tier
Reasoning levelsextended thinking (budget_tokens)none, low, medium, high, xhigh, max
Modalitiestext, imagetext, image
API model idclaude-haiku-4-5-20251001gpt-6-luna
ReleasedOctober 15, 2025September 22, 2026
Artificial Analysis Intelligence Index (2026-09-26)16.9Not verifiedUnverified
Artificial Analysis Intelligence Index [max] (2026-09-26)Not verifiedUnverified37.3
SWE-bench Verified (2026-02-17)66.6Not verifiedUnverified
Terminal-Bench (2025-10-15)40.21Not verifiedUnverified
DeepSWE 1.1 [max] (2026-09-22)Not verifiedUnverified66.6

Prices are USD per million tokens at standard rates, excluding batch and caching discounts. Bold indicates the better figure where one is objectively better. Values we could not confirm from the provider are shown as “Not verified” rather than estimated.

Benchmark receipts

Where each score comes from, and how far it can be compared across models.

Pricing tiers

Claude Haiku 4.5: Standard $1/$5 per MTok; cache reads 10% of base input. 200K context (vs 1M on Opus 5.5 and Sonnet 5).

GPT-6 Luna: Direct successor to GPT-5.6 Luna at half the price. Cached input $0.01/MTok; cache writes $0.125. Above 272K input the whole request bills $0.20/$0.75 ($0.02 cached). Batch/Flex $0.05/$0.25; Fast mode $0.20/$1.00. Knowledge cutoff May 18 2026.

BudgetRecord checked September 26, 2026

Claude Haiku 4.5

Claude Haiku 4.5 is Anthropic's fastest, cheapest tier for high-volume classification and extraction.

Best for

  • High-volume classification
  • Routine extraction
  • Latency-sensitive stacks

Watch out

No adaptive thinking (manual extended thinking via budget_tokens only); 200K context. Anthropic lists 2026-10-15 as the earliest possible retirement date, and Haiku 5.5 is announced but not released.

BudgetRecord checked September 26, 2026

GPT-6 Luna

GPT-6 Luna is OpenAI's cheapest current model at $0.10/$0.50 — the direct successor to GPT-5.6 Luna at half the price, with the full 1.05M-token context.

Best for

  • High-volume chat and extraction
  • Classification
  • Cost-capped agent loops

Watch out

Small tier: it matches GPT-5.6 Luna on the Artificial Analysis index but sits well below GPT-6 Sol on hard reasoning; the DeepSWE figure is vendor-reported at max effort.

When the cheaper one wins

GPT-6 Luna is cheaper on output at $0.50 per million tokens against $5 for Claude Haiku 4.5 — about 10×. Use the cheaper tier for classification, extraction, summarisation, and any task where the expensive model’s extra score does not change the accepted output. The expensive one only pays if your hardest task actually fails on the cheap tier. These are standard-tier API rates, excluding batch and cache discounts.

Run the model picker

Evidence confidence: High

How strong and complete the evidence behind this comparison is — not a prediction of which model is better.

  • Pricing verified on both sides — Input and output rates are verified for both models.
  • 4/5 core specs verified on both sides — Not published for at least one side: parameter count.
  • 1 shared named benchmark with differing scores — Measured on: Artificial Analysis Intelligence Index.
  • Verified within the last 90 days — Newest catalog check was 2 days ago.
  • Both models carry source citations — Each side has at least two catalog sources on record.

Source receipts

Each catalog figure was checked against the provider or an independent second source on the date shown.

Related comparisons

Diving deeper on one model? Claude Haiku 4.5 · GPT-6 Luna

Common questions

Claude Haiku 4.5 vs GPT-6 Luna

Answered from the verified figures on this page rather than general guidance.

Is Claude Haiku 4.5 or GPT-6 Luna cheaper for input?
GPT-6 Luna is cheaper at $0.10 per million input tokens, against $1 for Claude Haiku 4.5 — roughly 10× the price. Output tokens usually dominate a real bill, so weigh the output rate more heavily than the input rate. These are base rates; Claude Haiku 4.5 has tiered pricing: Standard $1/$5 per MTok; cache reads 10% of base input. 200K context (vs 1M on Opus 5.5 and Sonnet 5). GPT-6 Luna has tiered pricing: Direct successor to GPT-5.6 Luna at half the price. Cached input $0.01/MTok; cache writes $0.125. Above 272K input the whole request bills $0.20/$0.75 ($0.02 cached). Batch/Flex $0.05/$0.25; Fast mode $0.20/$1.00. Knowledge cutoff May 18 2026.
Is Claude Haiku 4.5 or GPT-6 Luna cheaper for output?
GPT-6 Luna is cheaper at $0.50 per million output tokens, against $5 for Claude Haiku 4.5 — roughly 10× the price. Output tokens usually dominate a real bill, so weigh the output rate more heavily than the input rate. These are base rates; Claude Haiku 4.5 has tiered pricing: Standard $1/$5 per MTok; cache reads 10% of base input. 200K context (vs 1M on Opus 5.5 and Sonnet 5). GPT-6 Luna has tiered pricing: Direct successor to GPT-5.6 Luna at half the price. Cached input $0.01/MTok; cache writes $0.125. Above 272K input the whole request bills $0.20/$0.75 ($0.02 cached). Batch/Flex $0.05/$0.25; Fast mode $0.20/$1.00. Knowledge cutoff May 18 2026.
Which has the larger context window, Claude Haiku 4.5 or GPT-6 Luna?
GPT-6 Luna accepts 1.05M tokens against 200K for Claude Haiku 4.5. This only matters if you routinely send very long documents or large codebases.
Do Claude Haiku 4.5 and GPT-6 Luna support the same reasoning levels?
Claude Haiku 4.5 exposes extended thinking (budget_tokens), while GPT-6 Luna exposes none, low, medium, high, xhigh, max.
Should I use Claude Haiku 4.5 or GPT-6 Luna?
Both sit in the budget tier, so the choice usually comes down to price and context rather than capability. Claude Haiku 4.5 suits high-volume classification; GPT-6 Luna suits high-volume chat and extraction.

Next step

Choosing between them

The verified figures that separate this pair, computed from the catalog rather than restated boilerplate.

  • Input price: GPT-6 Luna costs $0.10 per 1M tokens versus $1 for Claude Haiku 4.5 — a 10x difference at the headline tier.
  • Context: GPT-6 Luna takes 1.05M against 200K for Claude Haiku 4.5 — only decisive if your prompts approach the smaller window.
Run the model pickerEstimate stack costAll model comparisons

Choosing a harness rather than a model — Cursor, Copilot, Claude Code, Windsurf, or Lovable? Compare agentic harnesses · Latest releases.