GPT-5.6 Terra
openai/gpt-5.6-terraGPT-5.6 Terra is the middle tier of OpenAI's GPT-5.6 reasoning family, with text and image input, and is described by OpenAI as a balanced model for everyday work; it roughly corresponds to the mini tier of earlier GPT-5 families. It suits day-to-day coding, analysis and agentic tasks that need solid reasoning without flagship-level depth. Choose GPT-5.6 Sol for the most demanding work, GPT-5.6 Luna for the highest-volume tasks, or Terra Pro for hard individual requests.
- Input price
- $1.80
$2.00USD / 1M tokens - Output price
- $10.80
$12.00USD / 1M tokens - Cache read
- $0.18
$0.20USD / 1M tokens - Cache write
- $2.25
$2.50USD / 1M tokens - Context window
- 1.1M
- Max output
- 128K
Specifications
- Input
- Text, image
- Output
- Text
Try the model
Playground
Write a prompt to try this model. Usage is billed at the prices shown.
Try a prompt
Add an image (optional)
Your response will appear here
Choose an example or write a prompt, then click Run.
Start building
Send your first request
Choose either supported API with unified authentication and usage tracking.
# The quoted heredoc keeps Unicode and shell metacharacters unchanged.
result=$(curl --fail-with-body --silent \
-X POST "https://api.sandbase.ai/v1/responses" \
-H "Authorization: Bearer $SANDBASE_API_KEY" \
-H "Content-Type: application/json" \
--data-binary @- <<'SANDBASE_JSON'
{
"model": "openai/gpt-5.6-terra",
"input": "Hello",
"max_output_tokens": 2048
}
SANDBASE_JSON
)
printf '%s\n' "$result"Questions
FAQ
How do I call OpenAI GPT-5.6 Terra through SandBase?
Create a SandBase API key, then send requests with the model ID "openai/gpt-5.6-terra" 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 cost?
$1.80 per 1M input tokens and $10.80 per 1M output tokens with the current 10% discount (list price $2 / $12), billed per request from your SandBase balance.
What is the context window of OpenAI GPT-5.6 Terra?
1.1M tokens of context, with up to 128K output tokens per response.
Which features does OpenAI GPT-5.6 Terra support?
OpenAI GPT-5.6 Terra 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 and the other models in the catalog; you do not need to sign up with OpenAI separately.