strapi/packages/strapi-plugin-upload/admin/src/utils/formatBytes.js

// Source: https://stackoverflow.com/questions/15900485/correct-way-to-convert-size-in-bytes-to-kb-mb-gb-in-javascript
function formatBytes(receivedBytes, decimals) {
  const bytes = receivedBytes * 1000;

  if (bytes < 1) {
    return '0B';
  }

  const k = 1024;
  const dm = decimals <= 0 ? 0 : decimals || 2;
  const sizes = ['B', 'KB', 'MB', 'GB', 'TB', 'PB', 'EB', 'ZB', 'YB'];
  const i = Math.floor(Math.log(bytes) / Math.log(k));

  return `${parseFloat((bytes / k ** i).toFixed(dm))}${sizes[i]}`;
}

export default formatBytes;