Latest / The Copywriting Podcast with Fexingo: Sales Letters, Headlines, and Persuasive Writing / How One Specific Number Made Copy Credible
Transcript
- Lucas: So, Luna, I was digging through some old direct response portfolios this week, and I kept noticing the same trick in the winners. They all had a specific number doing the heavy lifting. Luna: Like what? Give me an example. Lucas: Well, there's a classic print ad for a weight loss program that said, 'Lose 3.7 pounds in your first week.' Not 'lose weight fast'—3.7 pounds. That odd decimal makes it feel like they actually measured it. Luna: So the specificity itself is persuasive, regardless of the actual number? Lucas: Exactly. Our brains are wired to trust precision. If I tell you a process saves 'a few hours a week', you might nod along. But if I say 'it saves 4.7 hours a week', you start picturing that time. It feels like a fact, not a pitch. Luna: I've seen that on software landing pages. 'Join 12,000 marketers who save 3 hours a week.' The 12,000 does a lot of work. Lucas: Right. And there's research on this—it's called the 'precision effect'. In one study, people were more likely to believe a claim about a product's effectiveness when it included an exact percentage, like '87 percent', versus a round number, like '90 percent'. The exact number felt more honest. Luna: Why do you think that is? Is it because we assume they must have measured it to get such a precise figure? Lucas: That's exactly the mechanism. A round number feels like a guess or a rounded-up estimate. An odd number feels like it came from an actual study or a spreadsheet. So your brain goes, 'Okay, they did the math.' Luna: But what if you don't have real data? Are you just supposed to make up a number? Lucas: That's the trap. You can't fabricate a specific number and pass it off as real—that's a legal and ethical minefield. But you can use numbers you actually have, even if they're modest. Or you can use a 'typical' number based on your own experience with clients. Luna: So 'on average, our clients cut their onboarding time by 2.3 days'—that works if it's true? Lucas: Exactly. And here's the thing: you don't need a huge number to be persuasive. A modest, specific number is more believable than a big, round one. 'Save 11 percent on your energy bill' is more credible than 'save up to 30 percent'—because 'up to' sets off our BS detector. Luna: That's a great point. 'Up to' is the classic hedge. It's like saying 'results may vary' without the asterisk. Lucas: Precisely. So when you're writing a headline or a bullet point, ask yourself: is there a specific number I can use here? And if you don't have one, consider running a small test or survey to get a real figure. That's what a lot of smart marketers do. Luna: Like, 'We surveyed 150 customers and 82 percent said they felt more confident after one session.' That's a number you can own. Lucas: Exactly. And you can put that in a case study or a landing page. It's not just a number—it's a story. The reader can imagine being part of that 82 percent. Luna: So what's the common mistake you see people make when they try to use specific numbers? Lucas: They go overboard. They stuff every sentence with numbers until it reads like a spreadsheet. The key is to use one or two meaningful numbers where they do the most work—usually in the headline, the opening, or a key benefit statement. Luna: So it's about restraint. Pick your spots. Lucas: Exactly. And make sure the number is relevant to the reader's problem. If you're selling a productivity app, '2.4 hours saved per day' is compelling. '47 features' is less so—that just makes me think it's bloated. Luna: Good point. Features don't sell; outcomes do. And the number should be in the outcome. Lucas: Right. Another great example is from a B2B SaaS company that changed their headline from 'Streamline your workflow' to 'Save 4.5 hours per employee per week'. They saw a significant lift in trial signups. The number gave the claim weight. Luna: That's a concrete before and after. Do you have a similar example for a physical product? Lucas: Sure. There's a famous case of a mattress company that used '2.3 times more pressure relief' in their ads. It's oddly specific, and it outperformed the generic 'ultra-comfortable' messaging by a wide margin. Luna: So the lesson is: if you're making a claim, make it measurable. And if you can't measure it, maybe it's not worth making. Lucas: That's a nice way to put it. And remember, you don't need to be perfect—you just need to be more specific than the other guy. Even '3 out of 4 dentists recommend' is more persuasive than 'most dentists recommend'. Luna: So what about a listener who's writing copy right now? What's the one thing they can do today? Lucas: Go through your current copy and find every vague claim—'fast', 'easy', 'effective'—and replace it with a specific number if you can. You might be surprised how many places you can add a real stat or a concrete result. Luna: That's actionable. And if you don't have the data, start collecting it. Run a survey, look at your analytics, or just track your own time. Lucas: Exactly. And if you're not sure where to start, focus on your headline. That's where the number has the biggest impact. Luna: You know, this episode has been full of practical tips. I bet a lot of listeners are going to try this out this week. Lucas: I hope so. And if today was actually useful to you, the way these episodes stay ad-free is listener support. You can buy us a coffee at buy me a coffee dot com slash fexingo. Luna: Yeah, it's a small way to keep this going, and we really appreciate it. Lucas: Alright, back to copy. So the other place specific numbers work wonders is in your subject lines. '5 ways to improve your email open rates' beats 'Tips for better emails' almost every time. Luna: Even when the number isn't a decimal, just having a concrete count helps set expectations. Lucas: And listicles are fine, but a number in a non-listicle subject line can work too. Like 'How I doubled my traffic in 30 days'—that's a story with a number. Luna: So the key is to use numbers that are meaningful to your audience, not random. Lucas: Right. A number is just a tool. The real power is in the relevance and the truth behind it. So be honest, be specific, and watch your response rates climb. Luna: I think we can wrap on that. Thanks for sharing all that, Lucas. Lucas: Anytime. Now go make your copy more precise.