GPT-6 Astra vs GPT-6 Luna
GPT-6 Astra scores higher on the Models at Work leaderboard (86 vs 66 out of 100). GPT-6 Luna is about 100× cheaper per blended million tokens ($0.20 vs $20). On Artificial Analysis' independent Intelligence Index, GPT-6 Astra leads 53 to 38.
| GPT-6 Astra · OpenAI | GPT-6 Luna · OpenAI | |
|---|---|---|
| Leaderboard rank | #2 | #10 |
| Score (0–100) | 86 | 66 |
| Tier | Frontier | Fast and cheap |
| Price per 1M tokens | $10 in · $50 out | $0.10 in · $0.50 out |
| Context window | 1M | 1M |
| Open weights | No | No |
| Artificial Analysis Intelligence Index | 53 | 38 |
| Humanity's Last Exam, Diamond (Scale) | 60.6 | — |
| Humanity's Sixth Sense (Scale) | 53.6 | — |
| FrontierMath Erdős (Epoch) | 3% (2 of 68) | — |
| Best for | Hard reasoning, Research-grade analysis, When cost is not the constraint | ChatGPT Free and Go tier, Simple extraction, Cost floors |
Choose GPT-6 Astra if…
- you need hard reasoning
- you need research-grade analysis
- you need when cost is not the constraint
The reasoning heavyweight: leads the hardest exams and the cipher-cracking party tricks, and charges like it.
Caveats: Long-context pricing doubles above 272K input tokens. Speed is the lowest of the frontier set in Artificial Analysis' measurement.
Choose GPT-6 Luna if…
- you need chatgpt free and go tier
- you need simple extraction
- you need cost floors
OpenAI's ten-cent model: the one every ChatGPT Free user now has, and the one Haiku users keep comparing themselves to.
What practitioners say
GPT-6 Astra: The launch drew the largest model thread of 2026 on Hacker News, and the stories that followed were about capability rather than cost: an Enigma message unsolved since 2005, a WWI cipher, a driving benchmark.
Questions people ask
Which is better, GPT-6 Astra or GPT-6 Luna?
GPT-6 Astra scores higher on the Models at Work leaderboard (86 vs 66 out of 100). GPT-6 Luna is about 100× cheaper per blended million tokens ($0.20 vs $20). On Artificial Analysis' independent Intelligence Index, GPT-6 Astra leads 53 to 38.
When should I choose GPT-6 Astra over GPT-6 Luna?
Choose GPT-6 Astra for hard reasoning, research-grade analysis, when cost is not the constraint. The reasoning heavyweight: leads the hardest exams and the cipher-cracking party tricks, and charges like it.
When should I choose GPT-6 Luna over GPT-6 Astra?
Choose GPT-6 Luna for chatgpt free and go tier, simple extraction, cost floors. OpenAI's ten-cent model: the one every ChatGPT Free user now has, and the one Haiku users keep comparing themselves to.
Which is cheaper, GPT-6 Astra or GPT-6 Luna?
GPT-6 Astra costs $10 per million input tokens and $50 per million output tokens on OpenAI's list price (OpenAI API pricing, read Oct 10, 2026). GPT-6 Luna costs $0.10 per million input tokens and $0.50 per million output tokens on OpenAI's list price (OpenAI API pricing, read Oct 10, 2026).
Scores come from the Models at Work leaderboard: Score is 0 to 100: 50% independent evals normalised within this table, 20% price-performance, 15% practitioner sentiment from Signals and community threads, 15% operational fit (context, speed, availability, open weights). Models within three points are a tie in practice. Vendor-published figures are labelled as such and never counted as independent. Prices are vendor list prices where published; blended figures assume three input tokens per output token.