GPT-5.6 Luna
openai/gpt-5.6-lunaGPT-5.6 Luna is the smallest, fastest tier of OpenAI's GPT-5.6 reasoning family, with text and image input; OpenAI says it roughly corresponds to the nano tier of earlier GPT-5 families. It is designed for high-volume workloads such as classification, extraction, routing, chat and lightweight agent steps where throughput and latency matter. Pick GPT-5.6 Terra or GPT-5.6 Sol when tasks need more capability, and the pro variant when a hard request needs more reasoning work.
- Input price
- $0.18
$0.20USD / 1M tokens - Output price
- $1.08
$1.20USD / 1M tokens - Cache read
- $0.02
$0.02USD / 1M tokens - Cache write
- $0.23
$0.25USD / 1M tokens - Context window
- 1.1M
- Max output
- 128K
Specifications
- Input
- Text, image
- Output
- Text
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Choose either supported API with unified authentication and usage tracking.
# The quoted heredoc keeps Unicode and shell metacharacters unchanged.
result=$(curl --fail-with-body --silent \
-X POST "https://api.sandbase.ai/v1/responses" \
-H "Authorization: Bearer $SANDBASE_API_KEY" \
-H "Content-Type: application/json" \
--data-binary @- <<'SANDBASE_JSON'
{
"model": "openai/gpt-5.6-luna",
"input": "Hello",
"max_output_tokens": 2048
}
SANDBASE_JSON
)
printf '%s\n' "$result"Questions
FAQ
How do I call OpenAI GPT-5.6 Luna through SandBase?
Create a SandBase API key, then send requests with the model ID "openai/gpt-5.6-luna" to Responses API (/v1/responses) or Chat Completions API (/v1/chat/completions) at https://api.sandbase.ai. The request examples on this page show the exact payload.
How much does OpenAI GPT-5.6 Luna cost?
$0.18 per 1M input tokens and $1.08 per 1M output tokens with the current 10% discount (list price $0.20 / $1.20), billed per request from your SandBase balance.
What is the context window of OpenAI GPT-5.6 Luna?
1.1M tokens of context, with up to 128K output tokens per response.
Which features does OpenAI GPT-5.6 Luna support?
OpenAI GPT-5.6 Luna supports vision (image input), reasoning, function calling, structured output. See Specifications above for the full list.
Do I need a separate OpenAI account?
No. One SandBase API key and balance gives you access to OpenAI GPT-5.6 Luna and the other models in the catalog; you do not need to sign up with OpenAI separately.