File Types and Fonts Supported in Box Content Preview

Content Preview supports viewing the following file types:


  • This section lists the file types supported through the Box Webapp and Box Mobile apps. To learn about the file types supported through Box Platform APIs, please see our developer documentation.
  • Preview is limited to files sized 500MB or smaller, except video files, which can be as long as 3.5 hours.
  • Using Box’s native spreadsheet viewer, Excel files are limited to files less than 100 columns and 100,000 rows.   Using the Excel Online viewer, the maximum file size that can be viewed is 5MB.

Text-Based Documents

'as', 'as3', 'asm', 'bat', 'c', 'cc', 'cmake', 'cpp', 'cs', 'css', 'csv', 'cxx', 'diff', 'doc', 'docx', 'erb', 'gdoc', 'groovy', 'gsheet', 'h', 'haml', 'hh', 'htm', 'html', 'java', 'js', 'json', 'less', 'log', 'm', 'make', 'md', 'ml', 'mm', 'msg', 'ods', 'odt', 'pages', 'pdf', 'php', 'pl', 'properties', 'py', 'rb', 'rst', 'rtf', 'sass', 'scala', 'scm', 'script', 'sh', 'sml', 'sql', 'txt', 'vi', 'vim', 'webdoc', 'wpd', 'xhtml', 'xls', 'xlsb', 'xlsm', 'xlsx', 'xml', 'xsd', 'xsl', 'yaml'



As Box relies on Excel Online to support the preview of .xlsm files, Box Preview is restricted to features supported by Excel Online.  More information about Excel Online preview on the Office Support site.


'gslide', 'gslides', 'key', 'odp', 'ppt', 'pptx' 


'ai', 'bmp', 'dcm', 'gif', 'eps', 'heic', 'jpeg', 'jpg', 'png', 'ps', 'psd', 'svg', 'tif', 'tiff', 'dcm', 'dicm', 'dicom', 'svs', 'tga'


  • Illustrator ('ai') files need to be saved in PDF-compatible mode in order to preview them in Box.
  • Images do not have the option to "print" from Box's preview. Images need to be downloaded to be printed.
  • Image preview for 'ai', 'eps', and 'ps' file types is available for Business level Box accounts and above upon requestFree or personal users can preview files owned by these accounts.


Audio Files

'aac', 'aif', 'aifc', 'aiff', 'amr', 'au', 'flac', 'm4a', 'mp3', 'ogg', 'ra', 'wav', 'wma'


Video Files

'3g2', '3gp', 'avi', 'm2v', 'm2ts', 'm4v', 'mkv', 'mov', 'mp4', 'mpeg', 'mpg', 'ogg', 'mts', 'qt', 'ts', 'wmv'



  • Video preview is available only to Business level Box accounts, and above. Free or personal users can preview video files owned by these accounts.
  • You can preview videos up to 3.5 hours in length.
  • AVCHD (Advanced Video Coding High Definition) is not supported in Preview. (Note: this is a specific video format, and does not refer to all high definition video. Several high-definition video formats are supported, as listed above.)

Flash/Mobile Video Files

'flv', 'swf' 

  • For security reasons, Flash files requiring network or script access are not supported in Preview.  
  • Support for Flash Video will be ending on September 5th, 2016. After this date, you will not be able to preview flash videos in Box, and will need to download and view them on your desktop.


3D (Graphics and Modeling) Files*

'3ds', 'box3d', 'obj', 'stl', 'fbx', 'dae', 'ply'



  • 3D preview is available only to Business Plus-level Box accounts and above. Free or personal users can preview 3D files owned by these accounts. 
  • The mobile app does not support 3D Preview.


Content Preview supports the following fonts:


Microsoft Office Docs

The full list of supported Microsoft Office Doc fonts is below.



1. Box will display any font embedded in the document itself, and reference the font if it is not embedded, so you will see it only if you have that font installed on your machine.  

2. Box Preview does not support Adobe PDF Portfolios at this time.


Other File Types

The remaining fonts not contained in the above sections are listed below:




Requesting Other Fonts

If you'd like to request that Box's Content Preview support a font not listed above, please let us know at  fonts@box.comBelow is the information we will need to complete the request: 
  • Complete details of the font
  • The font license agreement
  • The font source/binary or a link to the font source/binary. 

Thank you for your feedback in helping us improve Box Preview.