tldr
Without punctuation, the most common spelling in casual use.
The semicolon is frequently dropped online.
slang term explained
TL;DR
Too long; didn't read — either a complaint or a one-line summary.
TL;DR
The short answer
What does TL;DR mean?
TL;DR does two opposite jobs. As a reply it dismisses a piece of writing as too long to bother with. As a heading it introduces the author's own summary, pre-empting that complaint by providing the short version.
Background
Where it comes from
The abbreviation comes from early internet forums, where it began purely as the dismissive reply. Writers then adopted it as a courtesy, putting a TL;DR at the top or bottom of a long post, and that constructive use is now the more common one.
In conversation
How to use it
Write your own TL;DR as a genuine one-sentence summary rather than a teaser. As a reply to someone else's post it is straightforwardly rude.
Read the spelling in context
Forms people confuse
TL;DW
Too long; didn't watch — the same idea applied to video.
Increasingly common as long-form video has grown.
in summary
The formal equivalent, appropriate where the abbreviation would not be.
Use this in a document a stranger will read.
Realistic examples
TL;DR in a sentence
“TL;DR: the deploy failed because of the cache, and it is fixed.”
“Nobody wants a TL;DR that is four sentences long.”
“Replying just “tldr” to a colleague's write-up is a choice.”
Tone & nuance
What it communicates
Depends entirely on who wrote it. Self-applied it is considerate; applied to somebody else's work it says their effort was not worth your time.
Common questions
TL;DR FAQ
What does TL;DR mean?
TL;DR does two opposite jobs. As a reply it dismisses a piece of writing as too long to bother with. As a heading it introduces the author's own summary, pre-empting that complaint by providing the short version.
Where did TL;DR come from?
The abbreviation comes from early internet forums, where it began purely as the dismissive reply. Writers then adopted it as a courtesy, putting a TL;DR at the top or bottom of a long post, and that constructive use is now the more common one.
How do you use TL;DR in a sentence?
Write your own TL;DR as a genuine one-sentence summary rather than a teaser. As a reply to someone else's post it is straightforwardly rude. For example: “TL;DR: the deploy failed because of the cache, and it is fixed.”
Is TL;DR safe to use at work?
Depends entirely on who wrote it. Self-applied it is considerate; applied to somebody else's work it says their effort was not worth your time. A slang term like this belongs in casual conversation. In support replies, documentation or anything a stranger may read later, write the plain meaning instead so nobody has to already be in on the reference.
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