The image can be the same on all five platforms. The words underneath it almost never should be — not because the platforms are so different, but because the people reading them are in different rooms. Here is what each one allows, what each one actually shows, and one line rewritten five ways.
What each platform allows
- Instagram. 2,200 characters, 30 hashtags. Only the first two lines show before “more”.
- Facebook Page. 63,206 characters. Nobody reads past the fourth line.
- X. 280 characters on a free account. Links count as 23.
- Threads. 500 characters. One topic tag per post, not a pile of hashtags.
- LinkedIn. 3,000 characters. The first two lines show before “see more”; the rest is for people who chose to keep reading.
The limits are the least of it. The number that matters is how much shows before the fold: two lines on Instagram and LinkedIn, four on Facebook, all of it on X and Threads. Whatever you need read has to be in those lines.
The same line, five ways
The line on the card is Rest is not a reward for finishing. Here is how the caption under it changes.
Rest is not a reward for finishing. You are allowed to stop before the list does. #rest #slowdown #mindfulness
Rest is not a reward for finishing. One small permission for tonight: the list will be there tomorrow, and so will you.
Rest is not a reward for finishing.
Rest is not a reward for finishing. Stop when you need to, not when the list does.
For anyone finishing the week on empty: Rest is not a reward for finishing. It is part of the work, not a reward for it. The people who last are the ones who learned this early.
Why they differ
Instagram is scrolled with a thumb, quickly, often with the sound off. The caption is a second beat after the picture — one more sentence, then the tags. The tags are for the algorithm, not the reader; three that describe the post beat thirty that describe the industry.
Facebook Pages are read by people who chose to follow you a while ago and are older, on average, than on any other platform. Write the version that reads like a sentence a person would say. No tags at all.
X gets the line and nothing else. Anything added is something to argue with. If the picture carries the line, the caption can be the line again; repetition is fine here because the picture may not load in the timeline.
Threads sits between the two. A little warmer than X, no hashtag pile, one thought after the line.
LinkedIn wants a reason for the post to exist at work. Open with who it is for, then the line, then one sentence of consequence. It is the only platform where a third sentence earns its place.
Doing this every day
Five captions for every post is the kind of thing that is done well for a week and then not at all. Two habits make it survive. Write the line first, on the card, and let the captions be variations on it rather than five blank pages. And keep the per-platform rules in one place — a note, a template, a tool — so the X version is short because something makes it short, not because you remembered.
That is what the composer does when it drafts: one line, five captions written against the rules above and against your brand’s own voice, each one editable, none of them posted until you read it.