GPT-5.1-Codex
openai/gpt-5.1-codexGPT-5.1-Codex is a version of OpenAI's GPT-5.1 optimized for agentic coding in Codex and similar environments, released in November 2025 with text and image input and text output. It targets autonomous, long-running software engineering work inside coding agents and tools, and OpenAI notes its underlying snapshot is updated over time. Pick it over general GPT-5.1 when building coding agents; OpenAI serves it through the Responses API only.
- Input price
- $1.25USD / 1M tokens
- Output price
- $10.00USD / 1M tokens
- Cache read
- $0.13USD / 1M tokens
- Context window
- 400K
- Max output
- 128K
Specifications
- Input
- Text, image
- Output
- Text
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Choose either supported API with unified authentication and usage tracking.
# The quoted heredoc keeps Unicode and shell metacharacters unchanged.
result=$(curl --fail-with-body --silent \
-X POST "https://api.sandbase.ai/v1/responses" \
-H "Authorization: Bearer $SANDBASE_API_KEY" \
-H "Content-Type: application/json" \
--data-binary @- <<'SANDBASE_JSON'
{
"model": "openai/gpt-5.1-codex",
"input": "Hello",
"max_output_tokens": 2048
}
SANDBASE_JSON
)
printf '%s\n' "$result"Questions
FAQ
How do I call OpenAI GPT-5.1-Codex through SandBase?
Create a SandBase API key, then send requests with the model ID "openai/gpt-5.1-codex" 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-5.1-Codex cost?
$1.25 per 1M input tokens and $10 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-5.1-Codex?
400K tokens of context, with up to 128K output tokens per response.
Which features does OpenAI GPT-5.1-Codex support?
OpenAI GPT-5.1-Codex 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-5.1-Codex and the other models in the catalog; you do not need to sign up with OpenAI separately.