ModelEfficient language models

GPT-6 Luna

GPT-6 Luna is OpenAI's efficient GPT-6 model with the API ID gpt-6-luna, a 1,050,000-token context window, 128,000 maximum output, text and image input, text output, and reasoning effort from none through max.

Why it matters

Luna makes long-context reasoning and the current OpenAI tool surface practical for high-volume workloads. Its low base price does not remove the 272K long-prompt multiplier, verification cost, or product-specific access differences.

Source-backed summary

OpenAI's launch and model page control the API contract. OpenAI's comparative quality and cost claims remain provider-attributed. Community discussions are useful for rollout and usage-limit questions but do not override official availability.

Primary use cases

Process high-volume focused tasks.
Run low-cost long-context extraction and classification.
Handle mechanical coding and maintenance with verification.
Serve as a first-pass route before Sol or Astra.

Lowest-priced GPT-6 API tier

Base rates are $0.10 input, $0.01 cached input, $0.125 cache write, and $0.50 output per million tokens. Above 272,000 input tokens, 2x input/cache and 1.5x output rates apply to the full request.

Access depends on the product surface

OpenAI lists Luna in the API, ChatGPT Work, and Codex. Free and Go access is specifically documented for the desktop app, while Chat rollout and paid-plan access follow separate boundaries. Check the actual account and client instead of generalizing one surface.

When Luna fits

Luna is a candidate for extraction, classification, focused coding, document processing, and first-pass agent work. Escalate tasks when your own evals show the lower-cost route misses requirements; price alone is not a quality guarantee.

Related concepts

Agent Traces

How to measure task success, retries, tool calls, latency, and escalation cost.

AI Model API

The contract behind model identity, limits, pricing, and endpoints.

Related entities

GPT-6 Sol

The stronger GPT-6 workhorse for complex coding and agent tasks.

GPT-6 Astra

The highest-capability GPT-6 tier.

Comparisons

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