GPT 4.1 Nano is OpenAI’s lowest‑cost, lightning‑fast text model in the GPT‑4.1 family, built for reliably handling large documents with minimal latency. It excels at high‑volume workflows like classifying support inquiries, tagging spreadsheet rows, or generating smart short‑form copy, from bullet summaries of meeting notes to head‑turning call‑to‑action lines in marketing. Though lightweight, it maintains strong instruction‑following accuracy and consumes ~75 % less cost per operation than GPT 4.1 Mini.