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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.

Instagram — 1 of 9

Instagram0 / 2,200
Y

yourname·30m

Instagram won’t take a text-only post. Attach a photo or a video.

128 likes

Your caption shows here.

View all 12 comments

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

LinkedIn0 / 3,000
Y

Your name· 1st

@yourname

30m·

Your post text shows here.

12812 comments · 4 reposts
LikeCommentRepostSend

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

Facebook0 / 63,206
Y

Your name

30m·

Your post text shows here.

12812 comments · 6 shares
LikeCommentShare

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

Twitter / X0 / 280
Y
Your name@yourname·30m

Your post shows here.

1241282.4K

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

Bluesky0 / 300
Y
Your name@yourname.bsky.social· 30m

Your post text shows here.

124128

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

TikTok0 / 2,200
TikTok will not take a text-only post. Attach a video, or photos for a carousel, and it plays here.

@yourname

Your caption shows here.

original sound - yourname

Y1281246Y

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
YouTube needs a video. Attach one and it plays here.

Your video title shows here

Y

Your name

1.2K subscribers

Subscribe
128ShareDownload

2,431 views · 1 hour ago

Your description 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
Y
Your name30m

Your post text shows here.

8 replies · 128 likes

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
Pinterest needs an image. The pin is the image, so attach one and it fills this frame.

Your pin title shows here

Your pin description shows here.

YYour name

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.

The name, picture and engagement numbers on these cards are placeholders. A post that hasn’t gone out has no likes. Everything else is drawn the way the platform draws it.

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

Write the post once. Synapse publishes it to all nine networks on your schedule, with each one’s rules already applied.

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