OpenAI: GPT-6 Luna API Pricing
OpenAI: GPT-6 Luna costs $0.100 per 1M input tokens and $0.500 per 1M output tokens (cache reads: $0.010). Context window: 1.1M. Prices verified 2026-10-21 · source
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⚠️ Long-context price tier applies
The headline price only applies below the first threshold. Past it, you pay more per token:
See all thresholds on the long-context tiers page.
Rebuilt daily from our snapshot archive — the chart appears once a model has 5+ snapshots of history.
From our own daily snapshot archive — independent of provider announcements.
Intelligence measures reasoning/knowledge/coding benchmarks. A high score with a low blended price = value pick; check the value chart to see where this model lands.
Token economics
| Token type | Price | vs base input |
|---|---|---|
| Standard input | $0.100 | — |
| Cache read | $0.010 | −90% |
| Cache write (5m) | $0.125 | +25% |
| Output | $0.500 | — |
| Web search tool | $10/1k searches | — |
Prompt caching stores repeated context server-side: reads cost far less, but writes carry a one-time premium.
Higher effort = deeper thinking = more reasoning tokens billed as output.
What would OpenAI: GPT-6 Luna cost you per month?
| Workload | Requests/mo | Avg tokens (in/out) | Est. monthly cost |
|---|---|---|---|
| Light chatbot | 10,000 | 800 / 400 | $2.80 |
| Coding agent | 5,000 | 8,000 / 2,000 | $9.00 |
| RAG pipeline | 30,000 | 4,000 / 500 | $19.50 |
| Doc summarizer | 2,000 | 20,000 / 1,000 | $5.00 |
Estimates use list prices without prompt caching. Caching can cut input cost by up to 90% on repeated context.
About OpenAI: GPT-6 Luna
GPT-6 Luna is the fast, cost-efficient model in OpenAI's GPT-6 series, positioned below GPT-6 Sol. It is suited for high-volume and latency-sensitive workloads such as chat, classification, and lightweight agentic...
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Popular head-to-heads — see all on the comparisons index.
Frequently asked questions
How much does OpenAI: GPT-6 Luna cost?
OpenAI: GPT-6 Luna costs $0.100 per 1M input tokens and $0.500 per 1M output tokens; cached input tokens cost $0.010 per 1M. Verified 2026-10-21 — provider source.
What is the context window?
1.1M tokens, with up to 128K output tokens per response. That's roughly 1313 pages of text in a single request.
Does it support prompt caching?
Yes — cached input is $0.010/1M, about 90% cheaper than standard input. Agents and RAG workloads with repeated context benefit most.
What's a cheaper alternative?
ScaleDown: Summarize saves about 87% on a typical workload with comparable quality.
Official resources
- OpenAI: GPT-6 Luna on OpenRouter — live endpoint, pricing source of record.
- Artificial Analysis leaderboard → — independent intelligence and performance rankings.
- OpenAI pricing → — first-party pricing and billing details.
- LMArena leaderboard → — independent human-preference rankings.
- Shred your current bill — paste a CSV and see if switching saves money.