GPT-5 Nano is the fastest, most cost-efficient member of the GPT-5 family, optimized for summarization, classification, and other simple high-volume tasks. It supports a 400,000-token input context with 128,000 output tokens, text and image inputs, and exposes streaming, function calling, structured outputs, and tool integrations including web search, file search, image generation, code interpreter, and MCP. OpenAI recommends GPT-5.4 Nano for new speed- and cost-sensitive workloads.
Chat Completions API
/api/v1/chat/completions
OpenAI-compatible endpoint with a messages array. Standard interface for chat-based interactions.
Responses API
/api/v1/responses
Native OpenAI Responses format with a simplified input parameter for single-turn requests.
These providers haven't been health-probed for this model yet. The router still routes around upstreams that fail live requests — uptime fills in once probe history accrues.
curl https://anyrouter.dev/api/v1/chat/completions \
-H "Authorization: Bearer $ANYROUTER_API_KEY" \
-H "Content-Type: application/json" \
-d '{
"model": "openai/gpt-5-nano",
"messages": [
{"role": "user", "content": "Say hi in 3 words."}
]
}'ANYROUTER_API_KEY — Dashboard → Keys{
"model": "openai/gpt-5-nano",
"messages": [
{
"role": "user",
"content": "Say hi in 3 words."
}
]
}Change sort, ZDR, effort, or pin a provider to add routing params.