How to Write a LinkedIn Hook That Earns the Expand (Your First Line Is the Whole Post)
You spent forty minutes on the post. The story is good, the lesson lands, the last line is the best thing you've written all month.
Almost nobody read past the first sentence.
That isn't a comment on your writing. It's how the feed works. LinkedIn shows a truncated preview and hides everything after it behind "see more". Until someone taps that link, your post is one line long. Every reaction, every comment, every profile visit that eventually turns into a lead has to get through that one line first.
Which makes the first line less like an opening and more like a door charge. You don't get to show the good part until it's paid.
What the feed actually shows
The cutoff moves. It depends on the device, the app version, whether the post has an image above it, and how LinkedIn is testing the feed that week. On a wide desktop screen you might get a couple of lines. On a phone, less. Nobody outside LinkedIn can give you an exact character count that holds everywhere, and anyone who quotes one to two decimal places is guessing.
What you can do is write to the tightest case. Around 120 characters is the length that survives essentially anywhere, which is roughly this sentence you're reading right now. If your opener is longer than that, assume the tail of it is hidden and check that the visible part still does the job on its own.
The practical version: whatever your first line is, imagine it cut in half. Does the surviving half make someone want the rest? If the interesting bit lives in the second half, you've put your hook behind your own paywall.
Why "write a strong hook" is useless advice
Every piece of LinkedIn advice tells you to open strong. Almost none of it says what strong means, so people reach for volume instead: a bigger claim, a bolder promise, a line borrowed from a swipe file that worked for someone whose audience isn't yours.
The result is a feed full of openers that sound identical. "Unpopular opinion." "Let's be honest." "I'm excited to announce." These read as templates because they are templates, and a reader who has scrolled past four of them today will scroll past your fifth without deciding to. They aren't rejecting your idea. They never got far enough to see one.
A first line earns the tap when it does one specific thing: it opens a gap the reader wants closed. Not a promise that something valuable follows, which is what a template does. An actual missing piece.
Three things reliably create that gap.
A number that doesn't add up. "I turned down a ₹4 lakh project last month" makes a reader want the reason. Specificity is doing the work, not the size of the figure. A concrete detail implies there's a real story behind it, and a vague one implies there isn't.
A stated cost. What something took from you, in units. Six months. Two clients. One relationship. Cost signals that the post is an account of something that happened rather than advice assembled from nowhere.
A position someone could disagree with. Not manufactured contrarianism, which reads as a bid for comments. A real thing you believe that a reasonable peer might not, stated plainly enough that they know immediately whether they're on your side.
Notice that all three are hard to fake, which is exactly why they work. The templates are easy to write, and readers have learned that easy openers precede empty posts.
The openers that quietly cost you reach
Some first lines fail for reasons that have nothing to do with how interesting they are.
Hashtags and links in the opening line. A link in the first line spends your most valuable real estate on something the reader can't act on yet, and outbound links tend to depress reach besides. Hashtags at the top read as filing rather than talking. Both belong below the fold if they belong anywhere.
Capital letters used for emphasis. ALL CAPS reads as shouting on a screen. It doesn't buy attention, it buys a scroll.
Warm-up before the point. "So I was thinking about something interesting this week and wanted to share it with my network." That's forty words of throat-clearing before the actual sentence, and the actual sentence is now hidden behind "see more". Cut every clause before the first interesting noun.
A summary of the post. "Here are five lessons from my first year consulting." That's a table of contents. It tells the reader exactly what they'll get, which means they can decide they don't need it without expanding. Leave something out.
Before and after
Before: I'm excited to announce that I've been working on something new for the past few months and can finally share it with you all.
After: I spent four months building the thing my clients kept asking me for. Two of them told me they wouldn't pay for it.
The first announces. The second opens a gap: which two, and what did you do about it?
Before: Consistency is the most underrated factor in growing on LinkedIn.
After: I posted every weekday for a year. The three posts that brought me clients were all written in under ten minutes.
The first is a claim anyone could make. The second is a claim only you could make, and it contradicts the effort story people expect.
Before: Here are 5 things I learned from losing my biggest client.
After: My biggest client left on a Tuesday. I'd known it was coming since March and did nothing.
The first previews the content. The second withholds it, and the admission at the end makes the reader want to know why.
Before: Unpopular opinion: most consultants undercharge for their work.
After: I doubled my rate and lost one client out of nine. The one who left had been the most work.
The first labels itself contrarian. The second just is, with numbers attached.
A self-check before you post
Read your first line by itself, with the rest of the post covered, and check five things:
- It survives truncation. Around 120 characters, so the point isn't sitting past the cutoff.
- It isn't a stock opener. If you've seen the phrase on someone else's post this month, it's spent.
- It contains something concrete. A number, a date, a named cost. Something that couldn't be copy-pasted into anyone else's post.
- No hashtags, no links. Those go at the bottom.
- Sentence case. No shouting.
If you'd rather have that checked for you, the free LinkedIn hook analyzer runs exactly these five checks on a line you paste in and tells you which one you're failing. It's the same scoring we use internally to decide whether an opening line is worth keeping.
Stop borrowing hooks. Start reusing your own.
Swipe files are how most people fix this, and they're the reason so many feeds sound the same. A hook that worked for a growth marketer with 80,000 followers is calibrated to their audience, their proof, their voice. Borrowed, it reads as costume.
Your own past winners are better raw material, and you already have them. Somewhere in your history is a post that pulled far more engagement than your median, and the reason usually starts with the first line. That line is a pattern you can run again on a different topic, in your voice, with proof you actually have.
The problem is nobody remembers their own winners. You'd have to scroll back through months of posts, compare engagement by hand, and notice what the good openers had in common. So the pattern sits there unused while you scroll someone else's swipe file.
That's the part we automated. FounderSkies watches which of your published posts actually perform, pulls the opening lines from the ones that clear the bar, and keeps them as a bank of proven hooks you can start from when you write the next post. Not templates from a stranger. Lines that already worked, on your audience.
Pair that with knowing which posts actually drove your leads and the guesswork mostly disappears. You write the opener, you see what it earned, and the ones that earn get reused.
Your first line is the whole post, right up until someone decides otherwise. Write it like the rest depends on it, because it does.