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-oss-20b
GPT 5.6 Luna vs gpt-oss-20b
Compare GPT 5.6 Luna from OpenAI and gpt-oss-20b 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-oss-20b+ Add model · 2/4
gpt-oss-20b
OpenAI · text → text
gpt-oss-20b is a 21-billion parameter open-weight model released by OpenAI under the Apache 2.0 license. Its core feature is a Mixture-of-Experts (MoE) architecture that uses only 3.6B active parameters, enabling low-latency inference and deployment on consumer GPUs. The model also supports fine-tuning, function calling, tool use, and structured outputs.
Input$0.11 /M
Output$0.55 /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-oss-20b
Input /M
$0.2
$0.11
Output /M
$1.2
$0.55
Cache read /M
$0.02
-
Context length
1,050,000
128,000
Max output
128,000
32,768
Time to First Token
5.0 s
0.1 s
Throughput
47.2 tok/s
2619.0 tok/s
Modalities
textimage
text
Supported Parameters
toolsthinkingstructured outputs
thinkingfunction callingstructured outputs
API Formats
chat_completions · responses
Released
July 9, 2026
August 5, 2025
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-oss-20b
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-oss-20b
Throughput (tok/s)
-
TTFT (s)
-
Uptime (%)
-
Cost calculator
Estimate your monthly bill for the same workload on each model.
gpt-oss-20b
$14.85 /mo
GPT 5.6 Luna
$30.00 /mo
Monthly = daily × 30. Discounted rates applied where a promotion is active.
FAQ
Which is cheaper: GPT 5.6 Luna, gpt-oss-20b?
gpt-oss-20b: $0.55/M output tokens; GPT 5.6 Luna: $1.2/M. Use the cost calculator above to estimate your own workload.
Which responds faster?
gpt-oss-20b: 0.1s 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-oss-20b accepts 128,000 input tokens. Maximum output per request is 128,000 tokens on GPT 5.6 Luna and 32,768 tokens on gpt-oss-20b.
Which one generates tokens faster?
gpt-oss-20b at 2619.0 tok/s and GPT 5.6 Luna at 47.2 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-oss-20b accepts text input and supports thinking, function calling and structured outputs.
Can I call GPT 5.6 Luna and gpt-oss-20b 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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