A JSON minifier is a tool or program that reduces the size of a JSON (JavaScript Object Notation) document by removing unnecessary whitespace, indentation, and other non-essential characters. The process, known as minification, results in a more compact representation of the JSON data. JSON minifiers are commonly used in web development to optimize data transfer and improve application performance by reducing file sizes during transmission over the network. The minified JSON remains structurally valid, ensuring seamless decoding and usability while minimizing the data footprint.