GPT-5.6 Terra

OpenAI · GPT-5.6 · workhorse · released Jul 9, 2026 · gpt-5.6-terra

GPT-5.6 family:GPT-5.6 Sol·GPT-5.6 Terra·GPT-5.6 Luna

Balanced tier of the GPT-5.6 series, between the flagship Sol and the cost-efficient Luna, for everyday coding, reasoning, and agent workloads.

Pricing

Input$2.50 / 1M checked Jul 19, 2026
Output$15 / 1M checked Jul 19, 2026

A Pro serving mode (reasoning.mode=pro) is available at the same list price.

Cost bandBalanced
Free tierNo free API tier.

Limits

Context window1M checked Jul 19, 2026
DeploymentOpenAI API
OpenAI-compatible APIYes
ModalitiesText, Image input, PDF input

Where it fits

Best forProduction assistants, coding, and agent backplanes at moderate cost.
Business fitThe mid-price default for teams on the OpenAI stack.

Capabilities

Reasoning modesFunction callingStructured outputsWeb searchMCP

Change history

Data

Last checkedJul 19, 2026
Cross-checked againstopenrouter.ai/openai/gpt-5.6-terra

Verify with provider documentation before committing spend. Report an error and it gets fixed with a logged correction.

Open in the comparison table JSON API