What Is a Reblog on Tumblr?
A reblog is not a share. It is a copy that lives on somebody else's blog, and that one difference explains most of how Tumblr behaves.
A reblog copies a Tumblr post onto your own blog, where your followers see it and can reblog it again. It is not a retweet: a retweet is a pointer back to the original, while a reblog is a new post on your blog carrying the whole chain of everyone who reblogged before you. That is why reblogs can be edited, why added commentary becomes part of the post forever, and why deleting the original can break what people see in every copy downstream.
The thing to understand is that a reblog has lineage, and a retweet does not.
On Twitter or Bluesky, a repost is a reference. The platform shows the original post inside your timeline, and if the author deletes it, every repost shows nothing - because there was only ever one post.
On Tumblr, each reblog is a genuine post on the reblogger's own blog. It contains the content, plus the stack of everyone who reblogged it before them, plus anything each of those people added. That is why a Tumblr post you have seen often has eleven usernames above it with jokes attached - you are reading the accumulated chain, not a quote.
The consequence people notice is deletion. Text in a reblog is copied into each post, so deleting the original leaves the text intact down the chain. Images are referenced from Tumblr's media servers, so deleting the original blog can leave every copy showing a broken image - the famous dead Tumblr post with nine hundred notes and no picture.
It also means you cannot un-say something. Once a post has been reblogged, those copies belong to other people's blogs, and deleting yours does not remove them.
Reblog, like and note: three words for different things
Tumblr shows a single number under a post called notes. It is the sum of likes, reblogs and replies, which is why it is not comparable to any other platform's engagement number.
A like registers on the post and goes nowhere else. It is the closest thing Tumblr has to a private bookmark that the author can see.
A reblog puts the post on your blog, where your followers see it. It is the only one of the three that distributes anything.
A reply adds a comment, visible in the notes view rather than in the post itself.
So a post with 4,000 notes could be 3,900 likes and 100 reblogs, or the reverse, and those are completely different outcomes. The notes view - clicking the number - breaks it down, and it is the only honest way to read how a post actually did.
Why the chain has no ceiling
There is no algorithm on Tumblr deciding how far a post goes. Each reblog reaches that person's followers, some of whom reblog, and so on, with nothing capping it and nothing expiring.
That is why Tumblr posts resurface. A post from 2015 reblogged today by somebody with an engaged following starts the chain again, in front of people who have never seen it, with the original author's blog still attached at the bottom.
It is also why posting more often does not help the way it does elsewhere. Frequency buys you more chances for a chain to start. It does not buy distribution, because there is no distributor.
Added commentary, and why it is permanent
When you reblog, you can add text, images or tags. Everyone downstream sees what you added, because it is baked into every copy made after yours.
This is the mechanic behind the shape of Tumblr humour - the post where the funny part is the fourth person's addition - and also behind its worst arguments, because a hostile addition travels forever attached to the original.
You can edit your own reblog afterwards. You cannot edit copies made from it, which are already independent posts on other people's blogs. In practice a correction never catches up with the version that spread.
What this means if you are trying to be seen
The number to care about is reblogs, not notes and not followers.
Followers decide who sees the post first. Reblogs decide whether it goes anywhere after that. Likes tell you people saw it and did not pass it on, which is useful information and not distribution.
The practical version: a post with 600 likes and 4 reblogs did not travel. A post with 40 likes and 30 reblogs is moving, and will probably still be moving next week. Those two look similar in the notes count and are opposite results.
The deletion problem, stated plainly
If you delete your original post, text reblogs survive and image reblogs often break, because the image was being served from your blog's media.
If you delete your whole blog, the same thing happens across everything you ever posted, and people who reblogged you years ago end up with broken posts they cannot fix.
This is worth knowing before a clear-out. It is also why long-running Tumblr users tend to privately archive rather than delete - not sentiment, but the knowledge that deletion reaches into other people's blogs in a way it does not on any other platform.
Questions people ask about reblogging
Is a reblog the same as a retweet?
No. A retweet points at the original post; a reblog creates a copy on your own blog carrying the chain of everyone before you.
That is why reblogs can have commentary added at each step and why deleting an original does not erase them the way deleting a tweet erases its retweets.
Do likes count as notes on Tumblr?
Yes. Notes is the total of likes, reblogs and replies.
Clicking the note count opens a breakdown, which is the only way to tell whether a post with 2,000 notes actually traveled or just got liked.
Can I delete a reblog of my post?
Not somebody else's. Their reblog is a post on their blog and only they can remove it.
You can delete your own original, which breaks images down the chain but leaves text intact.
Why do old Tumblr posts have broken images?
Because the original blog was deleted and the images were being served from it.
Text copies into each reblog, images are referenced. It is the most visible consequence of the copy-with-lineage design.
Keep reading
- add reblogs to a post — Since reblogs are the only thing that carries a post anywhere on Tumblr, you can add reblogs to a post - which puts it on other blogs, without any promise that the chain continues from there.
- what happened to Tumblr — The reblog mechanic is also why what happened to Tumblr did not play out the way a feed-based platform's decline would.