GPT-5.6 Terra

Available

An OpenAI model with a 1.05M-token context window, image input and tool calling. On the OpenAI API since July 9, 2026.

Access details: OpenAI API

The model ID to use in API requests.

gpt-5.6-terra

Updated Oct 20, 2026

Sources & notes

Capabilities & limits

Context window: 1.05M
Maximum output: 128K
Image input: Supported
Tool calling: Supported
Structured output: Supported

Pricing

USD / 1M tokens

Input: $2.00
Output: $12.00

Standard rates per million tokens. Discounts and long-context rates, where offered, are on OpenAI's pricing page.

Full rate card 8 rates

All prices in USD.

Short-context input

$2.00 per 1M tokens

prompt ≤ 272K input tokens

Short-context output

$12.00 per 1M tokens

prompt ≤ 272K input tokens

Cached input

$0.20 per 1M tokens

prompt ≤ 272K input tokens

Cache writes

$2.50 per 1M tokens

prompt ≤ 272K input tokens

Long-context input

$4.00 per 1M tokens

prompt > 272K input tokens
rate applies to the full request

Long-context output

$18.00 per 1M tokens

prompt > 272K input tokens
rate applies to the full request

Long-context cached input

$0.40 per 1M tokens

prompt > 272K input tokens
rate applies to the full request

Long-context cache writes

$5.00 per 1M tokens

prompt > 272K input tokens
rate applies to the full request

Other tiers per 1M tokens (short context): Batch: $1 input / $6 output / $0.1 cached; Flex: $1 input / $6 output / $0.1 cached; Fast mode: $4 input / $24 output / $0.4 cached. Regional processing (data residency) endpoints add a 10% uplift. Cache writes are billed at 1.25x the uncached input rate. Terra prices were cut 20% on July 30, 2026.

Price history

Sep 13, 2026

Input $2.00 per million tokens

Sep 23, 2026

Input $2.00 per million tokens

Sep 13, 2026

Output $12.00 per million tokens

Sep 23, 2026

Output $12.00 per million tokens

Technical details

Parameters: Not published
Active parameters: Not published
Architecture: Not published
Training / knowledge cutoff: Feb 16, 2026
Input modalities: Text, image
Output modalities: Text

From OpenAI

Official announcement ↗

Release & lifecycle

First available: Jul 9, 2026
available: As of Sep 13, 2026
available: As of Oct 20, 2026