Write it once. See it on every platform.
Type below and watch the same post render as X, Bluesky, Threads and LinkedIn, each counted against its own real limit.
Nothing is uploaded. The counts and renders happen in your browser, using the same code that decides whether a real LetterBox post is allowed to send.
John Doe
@johndoe
· Mar 14Shipped a small thing today: one box that shows your post the way every platform will actually render it.
Try it: https://letterbox.social/tools/social-media-post-preview
The counts disagree on purpose. X bills any link at 23 characters no matter how long it is.
John Doe
@johndoe
· Mar 14Shipped a small thing today: one box that shows your post the way every platform will actually render it.
Try it: https://letterbox.social/tools/social-media-post-preview
The counts disagree on purpose. X bills any link at 23 characters no matter how long it is.
John Doe
2 Std.Shipped a small thing today: one box that shows your post the way every platform will actually render it.
Try it: https://letterbox.social/tools/social-media-post-preview
The counts disagree on purpose. X bills any link at 23 characters no matter how long it is.
John Doe
· 3rdShipped a small thing today: one box that shows your post the way every platform will actually render it.
Try it: https://letterbox.social/tools/social-media-post-preview
The counts disagree on purpose. X bills any link at 23 characters no matter how long it is.
1,462Why the counts disagree.
Most character counters call the equivalent of text.length and stop there. That answer is wrong on X, which is the one platform where being wrong gets your post rejected.
per link, on X
X rewrites every URL to a fixed length, so a 120-character link costs the same as a short one.
per emoji or CJK character
On X, anything outside a few Latin and punctuation ranges bills double. Most counters miss this.
everywhere else
Bluesky, Threads and LinkedIn count plain characters, which is why their numbers track your typing.
Questions about counts and previews.
Why do the character counts differ between platforms?
Because the platforms count differently. X does not count characters, it counts weight: every link bills as 23 characters no matter how long it is, and CJK characters and emoji cost 2 each. The other three count plain characters. A post that fits X by raw length can still be rejected by X.
What are the current character limits?
X allows 280 on a free account and 25,000 on any paid tier. Bluesky allows 300, Threads allows 500, and LinkedIn allows 3,000. This tool counts against the free X limit by default. Flip the "with Premium" toggle on the X card to count against 25,000 instead.
Is my text sent anywhere?
No. Everything runs in your browser. Nothing is uploaded, stored, or logged.
Are these the real previews?
Yes. This page mounts the exact preview components the LetterBox editor uses, so the render here cannot drift from what the product shows you before publishing.
Now schedule it without leaving the tab.
LetterBox keeps this preview beside you while you write, then publishes the post to X, Bluesky, Threads and LinkedIn on the schedule you set.
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