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See one caption the way each network will actually show it, including exactly where every platform cuts it off behind a “more” link.

0 characters
Image (optional)
Stays on your device.
Instagram0 / 2,200
YYour nameYour location
Instagram will not take a text-only post

Your caption shows here.

Shows in full, under the roughly 125-character cut-off.

LinkedIn0 / 3,000
YYour nameYour headline · Now

Your caption shows here.

Shows in full, under the roughly 140-character cut-off.

Facebook0 / 63,206
YYour nameJust now

Your caption shows here.

Shows in full, under the roughly 477-character cut-off.

Twitter / X0 / 280
YYour name@yourname · now

Your caption shows here.

Nothing to cut: a post that fits the 280-character limit is shown in full in the timeline.

Bluesky0 / 300
YYour name@yourname.bsky.social · now

Your caption shows here.

Nothing to cut: 300 characters is short enough to show in full.

TikTok0 / 2,200
YYour name@yourname
TikTok will not take a text-only post

Your caption shows here.

TikTok shows a line or two of caption over the video and hides the rest. Where it cuts depends on the video and the device rather than a character count we can quote.

YouTube0 / 5,000
YYour nameYour channel · Just now
YouTube will not take a text-only post

Your caption shows here.

YouTube collapses the description after roughly the first few lines under the player. That is a line count that moves with the window width, not a character figure.

Threads0 / 500
YYour name@yourname · now

Your caption shows here.

Threads does collapse very long posts, but we have no character figure for it we would stand behind, so the caption is shown in full here.

Pinterest0 / 500
YYour nameYour board
Pinterest will not take a text-only post

Your caption shows here.

Pinterest collapses longer descriptions in the pin, but we have no figure for it we would stand behind, so the description is shown in full here.

Where each network cuts your caption

  • 125Instagram, before “more”
  • 140LinkedIn on mobile
  • 477Facebook
  • 6 of 9publish no figure at all

Two different lines run through a caption. The hard limit, where a network refuses the post, is exact and comes from the same table Synapse publishes with. The cut-off, where it hides the rest but still accepts it, is published by nobody, shifts with screen width and moves when a feed is redesigned. So the limits here are firm, the cut-offs are marked approximate, and six platforms show no figure rather than an invented one.

Common questions

Where do the cut-off points come from?
No platform publishes them, so these are approximations measured from real posts: about 125 characters on Instagram, about 140 on LinkedIn mobile, about 477 on Facebook. They move when a feed is redesigned.
Why do some platforms show no cut-off at all?
Because we have no figure for them we would stand behind. They collapse long text by lines and layout rather than a character count anyone can quote. Inventing one would look more complete and be worth less.
Are the character limits approximate too?
No. Those are exact, from the same table Synapse enforces when it publishes. Only the cut-offs are approximate, and every card says so.
Is my caption or image uploaded anywhere?
No. Everything runs in your browser. The image is read straight from your device and never sent to a server.
Why does X show a different character count?
X counts any link as a flat 23 characters and each emoji or CJK character as 2, so its number can read higher than the plain count above.

Stop doing this by hand

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