gpt-oss-120b
openai/gpt-oss-120bgpt-oss-120b is OpenAI's largest open-weight reasoning model, released in August 2025 under the Apache 2.0 license: a 117B-parameter mixture-of-experts model with 5.1B active parameters that fits on a single 80GB GPU. OpenAI positions it for production, general-purpose and high-reasoning use, with adjustable low, medium or high reasoning, full chain-of-thought access, and native function calling, browsing, Python execution and structured outputs. It is text-only and can be self-hosted or fine-tuned.
- Input price
- $0.04USD / 1M tokens
- Output price
- $0.18USD / 1M tokens
- Context window
- 131.1K
- Max output
- 131.1K
Specifications
- Input
- Text
- Output
- Text
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Choose either supported API with unified authentication and usage tracking.
# The quoted heredoc keeps Unicode and shell metacharacters unchanged.
result=$(curl --fail-with-body --silent \
-X POST "https://api.sandbase.ai/v1/responses" \
-H "Authorization: Bearer $SANDBASE_API_KEY" \
-H "Content-Type: application/json" \
--data-binary @- <<'SANDBASE_JSON'
{
"model": "openai/gpt-oss-120b",
"input": "Hello",
"max_output_tokens": 2048
}
SANDBASE_JSON
)
printf '%s\n' "$result"Questions
FAQ
How do I call OpenAI gpt-oss-120b through SandBase?
Create a SandBase API key, then send requests with the model ID "openai/gpt-oss-120b" 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-oss-120b cost?
$0.04 per 1M input tokens and $0.18 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-oss-120b?
131.1K tokens of context, with up to 131.1K output tokens per response.
Which features does OpenAI gpt-oss-120b support?
OpenAI gpt-oss-120b supports 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-oss-120b and the other models in the catalog; you do not need to sign up with OpenAI separately.