Made with php, and PhpSpreadsheet https://github.com/PHPOffice/PhpSpreadsheet
1 . Clone repository
git clone git@github.com:antonshell/php_xlsx_to_json.git
2 . Install dependencies
composer install
1 . Set filenames in convert.php
$inputFileName = './demo.xlsx';
$outputFileName = './data/demo.json';
2 . Convert to json
php convert.php