uppy/src/utils/mimeTypes.js

module.exports = {
  'md': 'text/markdown',
  'markdown': 'text/markdown',
  'mp4': 'video/mp4',
  'mp3': 'audio/mp3',
  'svg': 'image/svg+xml',
  'jpg': 'image/jpeg',
  'png': 'image/png',
  'gif': 'image/gif',
  'yaml': 'text/yaml',
  'yml': 'text/yaml',
  'csv': 'text/csv',
  'avi': 'video/x-msvideo',
  'mks': 'video/x-matroska',
  'mkv': 'video/x-matroska',
  'mov': 'video/quicktime',
  'doc': 'application/msword',
  'docm': 'application/vnd.ms-word.document.macroenabled.12',
  'docx': 'application/vnd.openxmlformats-officedocument.wordprocessingml.document',
  'dot': 'application/msword',
  'dotm': 'application/vnd.ms-word.template.macroenabled.12',
  'dotx': 'application/vnd.openxmlformats-officedocument.wordprocessingml.template',
  'xla': 'application/vnd.ms-excel',
  'xlam': 'application/vnd.ms-excel.addin.macroenabled.12',
  'xlc': 'application/vnd.ms-excel',
  'xlf': 'application/x-xliff+xml',
  'xlm': 'application/vnd.ms-excel',
  'xls': 'application/vnd.ms-excel',
  'xlsb': 'application/vnd.ms-excel.sheet.binary.macroenabled.12',
  'xlsm': 'application/vnd.ms-excel.sheet.macroenabled.12',
  'xlsx': 'application/vnd.openxmlformats-officedocument.spreadsheetml.sheet',
  'xlt': 'application/vnd.ms-excel',
  'xltm': 'application/vnd.ms-excel.template.macroenabled.12',
  'xltx': 'application/vnd.openxmlformats-officedocument.spreadsheetml.template',
  'xlw': 'application/vnd.ms-excel'
}