GPT 5.6 Luna
OpenAI · text, image → text
GPT-5.6 Luna is designed for cost-sensitive, high-volume workloads. It roughly corresponds to the nano model tier used in earlier GPT-5 families.
Input$0.2 /M
Output$1.2 /M
Cache read$0.02 /M
← ModelsGPT 5.6 LunaGPT 6 Astra
GPT 5.6 Luna vs GPT 6 Astra
Compare GPT 5.6 Luna from OpenAI and GPT 6 Astra from OpenAI on key metrics including benchmarks, price, context length, and other model features. Access both models and hundreds of others through the AIHubMix API.
GPT 5.6 LunaGPT 6 Astra+ Add model · 2/4
GPT 6 Astra
OpenAI · text, image → text
GPT-6 Astra is OpenAI's newest and most intelligent model, with industry-leading performance in computer operations, web browsing, software engineering, scientific research, and professional work. It excels at executing multi-step workflows across code, browsers, and various professional software. Astra can achieve better results with significantly fewer output tokens, making its estimated API cost per task lower.
Input$10 /M
Output$50 /M
Cache read$1 /M
Pricing & Specifications
Prices are per million tokens. Time to First Token and throughput are rolling averages measured on AIHubMix.
GPT 5.6 Luna
GPT 6 Astra
Input /M
$0.2
$10
Output /M
$1.2
$50
Cache read /M
$0.02
$1
Context length
1,050,000
1,050,000
Max output
128,000
128,000
Time to First Token
5.0 s
9.8 s
Throughput
47.2 tok/s
32.7 tok/s
Modalities
textimage
textimage
Supported Parameters
toolsthinkingstructured outputs
toolsthinkingstructured outputs
API Formats
chat_completions · responses
chat_completions · responses
Released
July 9, 2026
September 5, 2026
Promotional prices show the discounted rate; see each model page for promotion windows.
Activity Past 30 Days
Daily traffic served through AIHubMix — how demand for each model is trending.
gpt-5.6-lunagpt-6-astra
Tokens / day
-
Requests / day
-
Performance Past 3 Days
Measured on real AIHubMix traffic, hourly buckets. Gaps mean no traffic in that hour.
gpt-5.6-lunagpt-6-astra
Throughput (tok/s)
-
TTFT (s)
-
Uptime (%)
-
Cost calculator
Estimate your monthly bill for the same workload on each model.
GPT 5.6 Luna
$30.00 /mo
GPT 6 Astra
$1,350 /mo
Monthly = daily × 30. Discounted rates applied where a promotion is active.
FAQ
Which is cheaper: GPT 5.6 Luna, GPT 6 Astra?
GPT 5.6 Luna: $1.2/M output tokens; GPT 6 Astra: $50/M. Use the cost calculator above to estimate your own workload.
Which responds faster?
GPT 5.6 Luna: 5.0s time to first token measured on AIHubMix; see the live performance charts above for how each model behaves across the day.
How large is each context window?
GPT 5.6 Luna accepts 1,050,000 and GPT 6 Astra accepts 1,050,000 input tokens. Maximum output per request is 128,000 tokens on GPT 5.6 Luna and 128,000 tokens on GPT 6 Astra.
Which one generates tokens faster?
GPT 5.6 Luna at 47.2 tok/s and GPT 6 Astra at 32.7 tok/s, measured as output throughput on AIHubMix — a separate metric from time to first token.
What inputs and capabilities does each model support?
GPT 5.6 Luna accepts text and image input and supports tool calling, thinking and structured outputs; GPT 6 Astra accepts text and image input and supports tool calling, thinking and structured outputs.
Can I call GPT 5.6 Luna and GPT 6 Astra with the same API key?
Yes. AIHubMix serves every model on this page behind one OpenAI-compatible endpoint, so switching between them is a one-line change to the model field — no second account, key or SDK.
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