AI Index

GPT-5.6 LunavsGPT-6 Luna

Both language models, compared at each maker’s own API list prices. Every figure links to its source.

Compare at your usage

Every model priced for the same request
Prompt per request
Cache hits
Batch
Service tier

8,000 tokens in, 2,000 out

GPT-5.6 Luna on OpenAI APIGPT-6 Luna on OpenAI API
Rate appliedBase rateBase rate
Inputper 1M tokens$0.20 $0.10
Cache readper 1M tokens$0.020 $0.010
Outputper 1M tokens$1.20 $0.50
Cost per request$0.004$0.0018
Per 1,000 requests$4.00$1.80

Every model is priced for the same request at its maker’s own list prices (each with its source and date), so bold marks the cheapest. A model that can’t serve the request is named, not ranked; a condition its seller doesn’t price says which rate was used.

Cost per request as prompts grow

2K tokens out, list price on each maker’s API. GPT-5.6 Luna charges $0.40 / $1.80 above 272K tokens. GPT-6 Luna charges $0.20 / $0.75 above 272K tokens.

0$0.050$0.100250K500K750K1Mprompt tokens per request272K8KGPT-5.6 Luna$0.004 at 8KGPT-6 Luna$0.0018 at 8K
  • GPT-5.6 Luna · OpenAI API
  • GPT-6 Luna · OpenAI API

Where each stands among all scored models

Each line runs from the lowest to the highest score on the board; the tick is the median.

Epoch Capabilities Index#30 vs #32 of 118GPT-6 Luna: 156.7GPT-5.6 Luna: 156.8LMArena Text#51 vs #63 of 163GPT-6 Luna: 1,441GPT-5.6 Luna: 1,453LMArena Text · Coding#51 vs #46 of 163GPT-6 Luna: 1,506GPT-5.6 Luna: 1,502LMArena Vision#40 vs #58 of 89GPT-6 Luna: 1,216GPT-5.6 Luna: 1,257
  • GPT-5.6 Luna
  • GPT-6 Luna

Key differences

GPT-5.6 LunaGPT-6 Luna
InputMaker’s official API · global · USD
$0.20 / 1M tokens OpenAI API pricing · as of Nov 2, 2026
$0.10 / 1M tokens OpenAI API pricing · as of Nov 2, 2026
OutputMaker’s official API · global · USD
$1.20 / 1M tokens OpenAI API pricing · as of Nov 2, 2026
$0.50 / 1M tokens OpenAI API pricing · as of Nov 2, 2026
Knowledge cutoff
Feb 2026 GPT-5.6 Luna · as of Nov 1, 2026
May 2026 GPT-6 Luna · as of Nov 2, 2026
Cache readMaker’s official API · global · USD
$0.020 / 1M tokens OpenAI API pricing · as of Nov 2, 2026
$0.010 / 1M tokens OpenAI API pricing · as of Nov 2, 2026
InputMaker’s official API · global · USD · Batch
$0.10 / 1M tokens OpenAI API pricing · as of Nov 2, 2026
$0.050 / 1M tokens OpenAI API pricing · as of Nov 2, 2026
Cache readMaker’s official API · global · USD · Batch
$0.010 / 1M tokens OpenAI API pricing · as of Nov 2, 2026
$0.005 / 1M tokens OpenAI API pricing · as of Nov 2, 2026

These differences use verified vendor specifications or each maker’s official API on the same region, currency, meter and billing conditions. Different conditions remain side by side in the full table; they do not establish which model is cheaper. Declared features describe support, not measured quality or a recommendation. Missing evidence does not mean a feature is unsupported.

Full comparison

GPT-5.6 Luna OpenAI GPT-6 Luna OpenAI
Overview
ReleasedJul 9, 2026 Sep 22, 2026
Open weights— —
Knowledge cutoffFeb 2026 May 2026
Specs
Context1.05M 1.05M
Max input922K 922K
Max output128K 128K
Input modalitiesText, Image Text, Image
Output modalitiesText Text
ReasoningYes Yes
Reasoning effortsnone, low, medium, high, xhigh, max none, low, medium, high, xhigh, max
Reasoning can be offYes Yes
Tool useYes Yes
Structured outputYes Yes
Pricing · per 1M tokens
Input price$0.20Also priced under other conditions: Batch, Flex tier, Fast tier, Prompts over 272K tokens $0.10Also priced under other conditions: Batch, Flex tier, Fast tier, Prompts over 272K tokens
Output price$1.20Also priced under other conditions: Batch, Flex tier, Fast tier, Prompts over 272K tokens $0.50Also priced under other conditions: Batch, Flex tier, Fast tier, Prompts over 272K tokens
Cache read price$0.020Also priced under other conditions: Batch, Flex tier, Fast tier, Prompts over 272K tokens $0.010Also priced under other conditions: Batch, Flex tier, Fast tier, Prompts over 272K tokens
Cache write pricefrom $0.25Also priced under other conditions: 12-hour cache, Prompts over 272K tokens, Batch, Flex tier, Fast tier30-minute cache $0.125Also priced under other conditions: 30-minute cache, 12-hour cache, Prompts over 272K tokens, Batch, Flex tier, Fast tier
Blended price (3 input : 1 output)$0.45 $0.20
Pricing under conditions · per 1M tokens
Input price, long prompts$0.40Prompts over 272K tokens $0.20Prompts over 272K tokens
Output price, long prompts$1.80Prompts over 272K tokens $0.75Prompts over 272K tokens
Batch input price$0.10Batch $0.050Batch
Batch output price$0.60Batch $0.25Batch
Flex tier input price$0.10Flex tier $0.050Flex tier
Flex tier output price$0.60Flex tier $0.25Flex tier
Cited scores
Epoch Capabilities Index156.8 156.7
LMArena Text1,453 xhigh effort1,441 max effort
LMArena Text · Coding1,502 xhigh effort1,506 max effort
LMArena Vision1,257 xhigh effort1,216 max effort
LMArena Text · Chinese1,478 xhigh effort1,483 max effort
Epoch AI · GPQA Diamond91.6% max effort90.5% max effort
Epoch AI · FrontierMath Tiers 1–382.1% max effort78.9% max effort

Headline prices may come from different channels, regions or tiers. Check each source before choosing a model; missing facts stay blank.

Model details and sources

Cited scores