There was a plumbing company in a town I'm fairly sure was invented for the invoice, and they paid for a beautiful landing page that converted at 0.8%. To brief a landing page so it converts, lock three things before any developer starts: the exact offer, one clear promise in the headline, and a single call to action.
The page was not the problem. Design and code come after those three are settled, not before. Most underperforming landing pages I get called in to fix were never briefed properly. The build was fine. The thinking that should have happened in a shared doc happened, badly, in the browser after launch. This post is the brief I wish every client handed me on day one.
Why does briefing matter more than the design?
Briefing matters more than the design because a landing page is a single argument, and the design only makes that argument louder. If the argument is fuzzy, a gorgeous page just fails faster and more expensively.
Across industries, median landing page conversion sits around 4% to 6%, and the top pages clear 10% or more (Unbounce's Conversion Benchmark Report is a good annual read on this). The gap between a 2% page and a 10% page is almost never the color of the button. It's whether the visitor understood, in about five seconds, what they get and what it costs them to say yes.
Here's the pattern I see. A client approves a design because it looks professional, then traffic arrives and nobody clicks. Now they're changing headlines live, arguing about button copy, and blaming the developer. Every one of those fights should have happened in the brief, where changes are free. Rewriting a headline in a Google Doc costs nothing. Rewriting it after a developer has hardcoded it into three components costs an afternoon (see How to Give Client Feedback on Web Design).
The cheapest place to fix a landing page is a document nobody has built yet. The most expensive is a live page with ad spend running against it.
What should a landing page brief actually contain?
A landing page brief should contain the offer, the audience, the single promise, the proof, the objections, and one call to action, all written in plain sentences before any layout exists. Everything else on the page is supporting cast.
Here is the full checklist I use with clients. If you can fill this in honestly, your developer can build something that converts. If you can't, no amount of design will save it.
| Brief element | The question it answers | Common mistake |
|---|---|---|
| The offer | What exactly is the visitor getting? | Describing the product, not the outcome |
| The audience | Who is this one page for? | Trying to speak to everyone at once |
| The promise | What's the headline in under 10 words? | A clever tagline nobody can decode |
| The proof | Why should they believe you? | No testimonials, numbers, or logos |
| The objections | What stops them saying yes? | Ignoring price, effort, or risk |
| The CTA | What is the one action? | Three competing buttons |
Notice there's nothing about fonts, colors, or animation in that table. Those are real decisions, and I care about them, but they're downstream. You brief the argument first.
How do you lock the offer before anything else?
You lock the offer by writing one sentence in the format "[outcome] without [pain point]" and refusing to build until that sentence is true and specific. The offer is the thing the visitor is trading their email or their money for.
The most common failure I see is a page that describes features instead of an outcome. "AI-powered scheduling with real-time sync" is a feature list. "Fill every open shift without the Sunday-night group text" is an offer. The second one tells a specific person their specific pain is about to end.
A few rules I hold clients to:
- Name one outcome, not five. If your product does many things, pick the one that matters to this audience and build the page around it. You can make more pages later.
- Be specific about the trade. Free trial? Waitlist? Paid? "Early access, locked-in founder pricing" converts differently than "Book a demo," and the whole page tone depends on which it is.
- Say the price, or say why you're not saying it. Hiding an obvious price creates suspicion. If the price is a strength, show it. If it needs context, explain the context on the page.
When the offer is genuinely clear, headline and CTA copy almost write themselves. When it isn't, you'll feel it as a vague ache every time you try to write a button label.
What copy has to be locked before development starts?
The copy that must be locked before development is the headline, the subheadline, and the call-to-action text, because the entire layout is built to frame those three. Everything else can be refined during the build; those three set the structure.
Think of it in layers. The headline states the promise. The subheadline explains, in one sentence, how you deliver it. The CTA names the action. If a developer has those three, they can wireframe a page that puts them in the right visual order, and they know how much room the hero needs.
A quick worked example for that plumbing company:
- Headline: "Emergency plumbing, someone at your door in 90 minutes"
- Subheadline: "Licensed local plumbers, flat call-out fee, no weekend surcharge"
- CTA: "Book a plumber now"
That took the pain (a burst pipe, right now), a believable specific (90 minutes, flat fee), and one obvious action. The old page said "Quality Plumbing Solutions For Your Home." One of those converts and one wins a beige award.
Nielsen Norman Group's research on how people read online is worth knowing here: users scan in an F-shaped pattern and mostly read headings and the first few words of a line. That's not a design detail. It's why the headline and the first line of copy do 80% of the work, and why they belong in the brief and not in a "we'll figure it out" pile.
How many calls to action should a landing page have?
A landing page should have one call to action, repeated. Not one button. One decision. You can put that same CTA in the hero, the middle, and the footer, but every button on the page should ask for the same yes.
The fastest way to tank a page is to give the visitor a choice between "Get early access," "Learn more," "Book a call," and "Follow us." Each option splits attention and lowers the odds any of them get clicked. A landing page is not your homepage. Its job is to move one specific person toward one specific action, and a homepage's job is to route many people to many places. Don't confuse the two.
If you genuinely have two audiences with two actions, that's two landing pages. It's cheaper to build a second page than to water down the first one until neither audience feels spoken to.
What happens if you skip the brief?
If you skip the brief, you pay for it after launch in the most expensive currency there is: live traffic and ad spend against a page that doesn't convert. The work doesn't disappear. It just moves to the worst possible time.
I've watched this happen enough to predict it. The page ships, it looks great, everyone's happy for a week. Then the numbers come in soft, and now you're doing the offer-and-headline thinking you skipped, except now it's a series of frantic edit requests, A/B tests with too little traffic to be significant, and a slowly souring relationship with whoever built it. The brief wasn't extra work. It was the same work, done early and cheaply (see slowly souring relationship with whoever built it).
That's the real argument for the brief. It doesn't add a step. It moves the hardest thinking to the point where changing your mind is free.
FAQ
What is a landing page brief?
A landing page brief is a short document that defines the offer, audience, headline promise, proof, objections, and single call to action for a page before any design or code begins. It's the argument the page will make, written in plain sentences.
How long should it take to write a landing page brief?
For a single page, a focused brief usually takes a few hours to a day of thinking, not weeks. The time goes into getting the offer and headline genuinely clear, which is hard, not into length. A good brief is often one to two pages.
Can a developer write the copy for me?
A developer or their team can help sharpen and structure the copy, and a good one will push back on a vague offer. But you, the business owner, have to supply the raw truth: who it's for, what they get, and why they should believe you. Nobody can invent your offer for you. If you want a second set of eyes on a brief before you build, that's exactly the kind of thing I'll walk through with you at Subsecond Studio.
Start with the offer sentence. Write "[outcome] without [pain point]" for your product, show it to three people in your target audience, and watch their faces. If they get it instantly, you're ready to brief the rest. If they squint, fix that before you spend a dollar on design.
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