How much does GPT-5.6 Luna cost?

GPT-5.6 Luna costs $0.20 per million input tokens and $1.20 per million output tokens on standard pricing; other tiers (Standard, Batch, Flex) are also available. A workload of 20M input and 5M output tokens a month is about $10.

What is the context length of GPT-5.6 Luna?

GPT-5.6 Luna accepts up to 1,050,000 tokens (1.1M) of input and can return up to 128,000 tokens in one response.

Does GPT-5.6 Luna support tool calling and structured outputs?

Yes, GPT-5.6 Luna supports function/tool calling and structured (JSON) outputs. Supported tools: Function calling, Structured outputs, JSON mode, Reasoning, Deterministic seed, Prompt caching.

What inputs and outputs does GPT-5.6 Luna support?

GPT-5.6 Luna accepts PDF, Image, Text as input and produces Text as output.

Which providers serve GPT-5.6 Luna?

GPT-5.6 Luna is available from 7 API providers: OpenAI, Azure, OpenAI, Azure, Amazon Bedrock, Azure, OpenAI. Prices can differ by provider.

When was GPT-5.6 Luna released?

GPT-5.6 Luna was released by OpenAI in 2026.

GPT-5.6 Luna

gpt-5.6-luna

API Provider site

Low-cost GPT-5.6 model; OpenAI's recommended replacement for GPT-5 nano and GPT-4.1 nano. Built by OpenAI.

Prices updated recently

Input price

$0.20

per 1M tokens · Standard

Output price

$1.20

per 1M tokens · Standard

Input limit

1.1M

tokens

Output limit

128K

tokens

Input formats

TextImageVideoAudioPDF

Output formats

TextImageVideoAudioPDF

Compare

GPT-5.6 Luna price history

2 price records since 9/25/2026

GPT-5.6 Luna cost calculator

Input20M tokens

Output5M tokens

$10/month

Standard pricing

Overview

What is GPT-5.6 Luna?

GPT-5.6 Luna is a text & reasoning and code & slms and vision model from OpenAI. Low-cost GPT-5.6 model; OpenAI's recommended replacement for GPT-5 nano and GPT-4.1 nano. Its 1.1M context window and $0.20 input price make it a candidate for cost-sensitive, high-throughput applications.

Code generationAgent workflowsImage understandingDocument analysis

Benchmarks

GPT-5.6 Luna benchmarks & speed

How GPT-5.6 Luna scores on standardized evaluations, and where it lands among every model we track.

37.3

Intelligence Index

Better than 82% of 153 models

126tok/s

Output speed

Better than 66% of 119 models

1235

DesignArena Elo

Better than 53% of 81 models

Reasoning

GPQA Diamond

91.1%

Graduate-level scientific reasoning · top 21%

HLE

39.5%

Humanity's Last Exam · top 22%

Coding

SciCode

53.6%

Python for scientific computing · top 36%

Latency & design

Time to first token: 106.4s
DesignArena win rate: 46.5%
Design battles judged: 19,101

Independent scores from Artificial Analysis and DesignArena · updated 10/8/2026. Higher is better; ranks compare against every model we track with that score.

Rates

GPT-5.6 Luna pricing

Pricing is based on token usage. Provider-specific caching, batch, regional, and tool charges may affect the final cost.

Input · Standard

$0.20

Per 1M tokens

Cached input · Standard

$0.02

Per 1M tokens

Capabilities

GPT-5.6 Luna Tools

Tools available when using GPT-5.6 Luna through supported provider APIs.

Function calling

Supported

Structured outputs

Supported

JSON mode

Supported

Reasoning

Supported

Built-in web search

Not supported

Log probabilities

Not supported

Deterministic seed

Supported

Parallel tool calls

Not supported

Prompt caching

Supported

Where to run it

GPT-5.6 Luna API providers

7 providers serve GPT-5.6 Luna. Prices are per 1M tokens; uptime is the last 24 hours.

Provider	Input	Output	Cached	Context	Uptime
OpenAI	$0.10	$0.60	$0.01	1.1M	100%
Azure	$0.20	$1.20	$0.02	1.1M	99.86%
OpenAI	$0.20	$1.20	$0.02	1.1M	99.99%
Azure	$0.22	$1.32	$0.02	1.1M	100%
Amazon Bedrock	$0.22	$1.32	$0.02	1.1M	99.9%
Azure	$0.22	$1.32	$0.02	1.1M	100%
OpenAI	$0.40	$2.40	$0.04	1.1M	100%

OpenAI

Input: $0.10
Output: $0.60
Cached: $0.01
Context: 1.1M
Uptime: 100%

Azure

Input: $0.20
Output: $1.20
Cached: $0.02
Context: 1.1M
Uptime: 99.86%

OpenAI

Input: $0.20
Output: $1.20
Cached: $0.02
Context: 1.1M
Uptime: 99.99%

Azure

Input: $0.22
Output: $1.32
Cached: $0.02
Context: 1.1M
Uptime: 100%

Amazon Bedrock

Input: $0.22
Output: $1.32
Cached: $0.02
Context: 1.1M
Uptime: 99.9%

Azure

Input: $0.22
Output: $1.32
Cached: $0.02
Context: 1.1M
Uptime: 100%

6 of 7

Strengths and limitations

Strengths

Low input cost at $0.20 per million tokens suits high-volume workloads.
1.1M context supports large documents, repositories and extended conversations.
Supports text & reasoning and code & slms and vision workloads in one model.

Limitations

Generated tokens cost 6× more than input tokens, which matters for verbose responses.
Large context capacity does not guarantee consistent retrieval across the entire prompt.
Arena Elo and MMLU-Pro are directional; test accuracy, latency and reliability on your own workload before committing.

Arena Elo, MMLU-Pro and pricing figures are illustrative; validate current vendor terms before purchase.

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Frequently asked questions about GPT-5.6 Luna

GPT-5.6 Luna is a text & reasoning and code & slms and vision model from OpenAI. Low-cost GPT-5.6 model; OpenAI's recommended replacement for GPT-5 nano and GPT-4.1 nano.