The Tumblr Backup app is ready for beta testing!

• Download (Mac OS X, requires 10.5 or higher)

Unlike other publishing sites’ approach to backups, our goal was to create a useful copy of your blog’s content that can be viewed on any computer, burned to a CD, or hosted as an archive of static HTML files.

Wherever possible, we use simple file formats. Our backup structure is optimized for Mac OS X’s Spotlight for searching and Quick Look for browsing, and we’ll try to use the same structure and achieve the same benefits on other platforms.

Release notes:

• Sorry, there’s no Windows version yet.
• The output is minimally styled in a plain theme to ensure complete backups, zero external requirements, and a consistent data structure. Custom theme code is included in the backup as a separate file.
• To view the backup in a browser, open the index.html file.
• Photosets are not yet fully downloaded.
• The following are not backed up:
  • Private tumblelogs
  • Submissions
  • Notes
  • Feed-imported posts
  • Audio files from reblogged posts
• You can launch the app every few days and re-run the backup in the same place, and it effectively performs an incremental media backup: image and audio files are only re-downloaded if they don’t already exist in the target folder. Text content and post data are re-downloaded in full every time.
• If you have private posts, be careful if you make the backup publicly available. Private posts are included in a private folder, and their images or audio files are included in the standard images and audio folders.
• Are you a programmer? Each post’s XML data, as specified by our API, is embedded inside an easily-parsed-out HTML comment in each post’s HTML file, in case you want to do anything cool with it.