Skip to content

GPT-5.6 Luna

OpenAI · released 9 Jul 2026 · proprietary API

Fastest, lowest-cost GPT-5.6 tier for high-volume work.

Context window

1.05M

1,050,000 tokens

Input price

$1

per 1M tokens

Output price

$6

per 1M tokens

Blended

$2.25

3:1 in:out mix

Weights

Proprietary

API only

Released

9 Jul 2026

OpenAI

Long-context / tier pricing>272K input billed at the long-context tier ($2 in / $9 out per 1M). Listed prices are the base rate for prompts up to ~200K tokens.

Where it ranks

Of 19 models tracked.

Cost to run

#9

of 19

Input price

#6(tied)

of 19

Context window

#1(tied)

of 19

See the full Frontier Index →

Compare with

The nearest models by blended cost to run.

Put it to work

Specs from BitByteCore's hand-verified Frontier Ledger (v2026-07-10, verified 21 Jun 2026). Model pricing moves fast — confirm with OpenAI before you rely on a figure.