AI adoption in Spain (2023-2025): A web-derived dataset based on LLMs

This article introduces a nationwide dataset that maps how 112,814 Spanish firms communicate and implement artificial intelligence (AI) on their corporate websites in 2023 and 2025, resulting in 225,628 firm-year observations. Using a systemic pipeline based on large language models (LLMs), website text is segmented, semantically filtered, and evaluated with a structured rubric to identify explicit evidence of AI use in internal processes and in products or services. The dataset offers a detailed portrait of AI adoption across regions (NUTS 3), industries, and firm size categories. For each province-sector-size combination, it reports whether firms adopt AI, whether they apply it internally, whether it is embedded in their offerings, and how many firms have valid website content. This multi-dimensional structure enables users to explore territorial patterns, sectoral differences, and size-related disparities in the uptake of AI. By providing indicators for two benchmark years, the dataset supports the study of how AI adoption evolves across the Spanish business landscape. It offers a reproducible and scalable foundation for research on technological diffusion, regional digitalisation, and industry-level transformation, and can be readily extended to future years or adapted to other countries.