GPT-5.6 Luna Pro

Name: OpenAI GPT-5.6 Luna Pro
Price: 0.2 USD
Availability: InStock
Author: OpenAI

openai/gpt-5.6-luna-pro

GPT-5.6 Luna Pro is the same GPT-5.6 Luna model, OpenAI's smallest GPT-5.6 tier, served in OpenAI's pro reasoning mode rather than as different weights. In pro mode the model performs more work on each request before returning a single final answer, which OpenAI says can improve reliability on difficult tasks at the expense of higher latency and token usage. Use it when Luna's speed tier is preferred but a particular request is hard; keep standard Luna for routine, high-volume traffic.

Use in agent Get API key

Input price: $0.20USD / 1M tokens
Output price: $1.20USD / 1M tokens
Context window: 1.1M
Max output: 128K

Production route

Try the model

Playground

Open playground

Input⌘ / Ctrl + Enter

Try a prompt

Prompt

Image URL or upload

Upload

1.1M context128K max outputVision

Input$0.20/MOutput$1.20/MCache read$0.02/MCache write$0.25/M

OutputReady

Your response will appear here

Choose an example or write a prompt, then click Run.

Model card

Specifications

Pricing

Input: $0.20 / 1M tokens
Output: $1.20 / 1M tokens
Cache read: $0.02 / 1M tokens
Cache write: $0.25 / 1M tokens

Context & modalities

Context window: 1,050,000 tokens
Max output: 128,000 tokens
Input: Text, image
Output: Text

Capabilities

Chat: Supported
Vision: Supported
Reasoning: Supported
Structured output: Supported
Function calling: Supported
Audio input: Not supported

Access

Provider: OpenAI
Model ID: openai/gpt-5.6-luna-pro
Execution: sync
Base URL: https://api.sandbase.ai
API: Responses API
Endpoint: /v1/responses
API: Chat Completions API
Endpoint: /v1/chat/completions

Start building

Send your first request

Choose either supported API with unified authentication and usage tracking.

Production API

Responses API endpoint

https://api.sandbase.ai/v1/responses

Model ID

openai/gpt-5.6-luna-pro

# 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 $SANDBASE_API_KEY" \
  -H "Content-Type: application/json" \
  --data-binary @- <<'SANDBASE_JSON'
{
  "model": "openai/gpt-5.6-luna-pro",
  "input": "Hello",
  "max_output_tokens": 2048
}
SANDBASE_JSON
)
printf '%s\n' "$result"

Choose your model

Compare models

All language models

Model	Context	Input / 1M	Output / 1M	Released
GPT-5.6 Luna ProThis model `OpenAI`	1.1M	$0.20	$1.20	Jul 9, 2026
GPT-6.1 Sol Pro `OpenAI`	1.1M	$2.00	$10.00	Sep 29, 2026
GPT-6.1 Sol `OpenAI`	1.1M	$2.00	$10.00	Sep 29, 2026
GPT-6 Luna Pro `OpenAI`	1.1M	$0.10	$0.50	Sep 22, 2026
GPT-6 Luna `OpenAI`	1.1M	$0.10	$0.50	Sep 22, 2026
GPT-6 Sol Pro `OpenAI`	1.1M	$2.00	$10.00	Sep 22, 2026

Questions

FAQ

How do I call OpenAI GPT-5.6 Luna Pro through SandBase?

Create a SandBase API key, then send requests with the model ID "openai/gpt-5.6-luna-pro" 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 Pro cost?

$0.20 per 1M input tokens and $1.20 per 1M output tokens, billed per request from your SandBase balance. Discounts, when available, are shown in the pricing on this page.

What is the context window of OpenAI GPT-5.6 Luna Pro?

1.1M tokens of context, with up to 128K output tokens per response.

Which features does OpenAI GPT-5.6 Luna Pro support?

OpenAI GPT-5.6 Luna Pro 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 Pro and the other models in the catalog; you do not need to sign up with OpenAI separately.