You can upload videos files as large as 100 MB directly to your Tumblr account. The length of a video file can be up to 5 minutes. To get started, go to your Tumblr Dashboard, choose Video and then click the Upload tab.
Your video on Tumblr can 5:00 minutes long, 100MB max .
Unlike Youtube where you to wait for the system to finish transcoding, videos uploaded to Tumblr will instantly show up in your blog.