The ID of the root post in a chain of reblogs ending in a final like or unlike. As an example, consider this sequence of events:

  1. User A posts a blog.
  2. User B reblogs user A's blog.
  3. User C reblogs user B's reblog.
  4. User D likes user C's reblog.

The tumblr.root.postid target contains the id of the user A's original post, no matter how long the chain of reblogs happens to be. For any of the reblogs in the chain, the tumblr.root.blogid target always refers back to the original.

Alternatively, the tumblr.root.blogid allows you to filter on the id of the blog that the root post appeared on.


  1. Filter for likes or unlikes of reblogs, perhaps in a chain, of any post mentioning "coffee" on any post in a specified list:

interaction.content contains "coffee" and
tumblr.root.postid in "12345678900, 88888888888, 98765432100"

Resource information

Target service: Tumblr

Type: string

Array: No

Always exists: No