GPT-5.6 Terra Pro

Name: OpenAI GPT-5.6 Terra Pro
Price: 2 USD
Availability: InStock
Author: OpenAI

openai/gpt-5.6-terra-pro

GPT-5.6 Terra Pro is the same GPT-5.6 Terra model, the balanced middle tier of OpenAI's GPT-5.6 family, served in OpenAI's pro reasoning mode instead of standard mode. Pro mode applies more model work to each request and returns a single final answer, which OpenAI says can improve reliability on difficult problems while increasing latency and token usage. It fits harder coding, review or analysis tasks where Terra's tier is preferred but extra quality on a single answer matters.

Use in agent Get API key

Input price: $2.00USD / 1M tokens
Output price: $12.00USD / 1M tokens
Context window: 1.1M
Max output: 128K

Production route

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Prompt

Image URL or upload

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1.1M context128K max outputVision

Input$2.00/MOutput$12.00/MCache read$0.20/MCache write$2.50/M

OutputReady

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Choose an example or write a prompt, then click Run.

Model card

Specifications

Pricing

Input: $2 / 1M tokens
Output: $12 / 1M tokens
Cache read: $0.20 / 1M tokens
Cache write: $2.50 / 1M tokens

Context & modalities

Context window: 1,050,000 tokens
Max output: 128,000 tokens
Input: Text, image
Output: Text

Capabilities

Chat: Supported
Vision: Supported
Reasoning: Supported
Structured output: Supported
Function calling: Supported
Audio input: Not supported

Access

Provider: OpenAI
Model ID: openai/gpt-5.6-terra-pro
Execution: sync
Base URL: https://api.sandbase.ai
API: Responses API
Endpoint: /v1/responses
API: Chat Completions API
Endpoint: /v1/chat/completions

Start building

Send your first request

Choose either supported API with unified authentication and usage tracking.

Production API

Responses API endpoint

https://api.sandbase.ai/v1/responses

Model ID

openai/gpt-5.6-terra-pro

# The quoted heredoc keeps Unicode and shell metacharacters unchanged.
result=$(curl --fail-with-body --silent \
  -X POST "https://api.sandbase.ai/v1/responses" \
  -H "Authorization: Bearer $SANDBASE_API_KEY" \
  -H "Content-Type: application/json" \
  --data-binary @- <<'SANDBASE_JSON'
{
  "model": "openai/gpt-5.6-terra-pro",
  "input": "Hello",
  "max_output_tokens": 2048
}
SANDBASE_JSON
)
printf '%s\n' "$result"

Choose your model

Compare models

All language models

Model	Context	Input / 1M	Output / 1M	Released
GPT-5.6 Terra ProThis model `OpenAI`	1.1M	$2.00	$12.00	Jul 9, 2026
GPT-6.1 Sol Pro `OpenAI`	1.1M	$2.00	$10.00	Sep 29, 2026
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GPT-6 Luna Pro `OpenAI`	1.1M	$0.10	$0.50	Sep 22, 2026
GPT-6 Luna `OpenAI`	1.1M	$0.10	$0.50	Sep 22, 2026
GPT-6 Sol Pro `OpenAI`	1.1M	$2.00	$10.00	Sep 22, 2026

Questions

FAQ

How do I call OpenAI GPT-5.6 Terra Pro through SandBase?

Create a SandBase API key, then send requests with the model ID "openai/gpt-5.6-terra-pro" to Responses API (/v1/responses) or Chat Completions API (/v1/chat/completions) at https://api.sandbase.ai. The request examples on this page show the exact payload.

How much does OpenAI GPT-5.6 Terra Pro cost?

$2 per 1M input tokens and $12 per 1M output tokens, billed per request from your SandBase balance. Discounts, when available, are shown in the pricing on this page.

What is the context window of OpenAI GPT-5.6 Terra Pro?

1.1M tokens of context, with up to 128K output tokens per response.

Which features does OpenAI GPT-5.6 Terra Pro support?

OpenAI GPT-5.6 Terra Pro supports vision (image input), reasoning, function calling, structured output. See Specifications above for the full list.

Do I need a separate OpenAI account?

No. One SandBase API key and balance gives you access to OpenAI GPT-5.6 Terra Pro and the other models in the catalog; you do not need to sign up with OpenAI separately.