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case-study 11 May 2026

How we built a $3 lead magnet for Post2Reach

The exact mechanism: why a free score made 113 people sign up in 30 days, and how CPA dropped from $30 to $2.50 on the best Meta Ads angle.

The LinkedIn SaaS market is saturated. Direct-pitch register CPA runs $25-40.

When we launched Post2Reach with a direct pitch ("generate your LinkedIn posts with AI"), we were paying $30+ register CPA on Meta Ads. The math didn't work: on a €23/mo Starter, you need 13 months of retention to break even. Too fragile.

The problem wasn't the product. It was the brief.

A LinkedIn visitor who sees an "AI for LinkedIn" ad has already received 50 identical messages this week. They scroll past. No reason to click, even less to hand over their email.

So we flipped the offer: instead of asking "sign up to use our product," we offered something concrete and self-contained that pushes them to give us their LinkedIn URL in exchange for an answer to a question they actually have.

> The triggering insight: every LinkedIn creator wonders "is my profile any good?". Nobody gives them an honest answer. That's exactly the vacuum the lead magnet fills.

Before / after

| Metric | Direct pitch | Score lead magnet | |---|---|---| | Register CPA (best angle) | $28-35 | $2.50 | | Entry friction time | 30s (direct signup) | 90s (LinkedIn URL → score) | | Post-signup engagement | Low ("they sold me") | High ("they taught me") | | Lead → trial conversion | 3-5% | 65% (score → signup same session) | | Cost per paying customer | $500-700 | $130 (and dropping) |

LinkedIn scoring: a 90-second audit that tells the truth

The user pastes their LinkedIn URL. Our AI scrapes the profile (photo, banner, headline, about, experience, recommendations, education, engagement), grades each of 9 criteria, and returns a score out of 100 plus a profile archetype (Strategist, Builder, Connector, etc.).

Why it works

  • Self-applicable — nothing to configure, just paste a LinkedIn URL.
  • Personal — the output is about YOU, not a generic case study. Average score is 62/100, so almost everyone learns they have "work to do" on 2-3 specific axes.
  • Ego-aligned — getting an archetype score ("you're a Strategist") flatters. Organic sharing is 3× higher than a product pitch.
  • Pre-qualified — people who spend 90s pasting their LinkedIn URL are serious prospects. They're not here to scroll.

The funnel, in numbers (last 30 days in prod)

| Step | Volume | Conversion | |---|---|---| | Landing /score visit | ~2,200 | ~$0.25/visit | | Submits LinkedIn URL | 66 | 3% | | Signs up after seeing score | 43 | 65% | | Total signups (all sources) | 113 | $2.50–$30 CPA | | Activates trial then paid | 5 | 4.4% trial → paid |

The key line is row 3: 65% of people who got a score sign up on the spot. That's 10-20× a cold signup rate. The lead magnet turns a curious visitor into an engaged user in under 5 minutes.

What makes a $3 lead magnet possible: 4 pillars

The score isn't the trick — anyone can build a quiz. What makes the CPA this low is the alignment of four technical and creative layers we iterated on for 8 weeks.

1. The "02-revelation" angle

The best-performing Meta ad isn't a pitch. It's a reveal: "your LinkedIn score is probably 50/100 — here's why." The audience clicks to validate an uncomfortable intuition.

2. Live scraping

The analysis isn't a 5-question quiz, it's a real Apify scrape of the profile in 8 seconds. The cinematic progress bar sells the AI's effort — the perceived investment justifies the result.

3. The "I tried" video format

The best Meta creatives are UGC "I tested this for 7 days, here's what happened" clips. Production cost: $0 (phone + 90s of footage). CTR 3.5× above a product carousel.

4. Meta CAPI cross-device

Server-side fbp + fbc cookies propagated via the Conversions API. Without it, Meta sees 0% of conversions and CPC stays at $4. Once wired in: Meta optimizes for REAL converting clicks → CPC drops to $0.90.

What we tried that did NOT work

  • 10-question quiz without scraping — 70% bounce. Too much effort for a generic answer.
  • Score without archetype — "67/100" alone says nothing. Adding "you're a Strategist" doubled signup conversion.
  • Testimonial ads — CPA $18. Nobody trusts testimonials on LinkedIn in 2026.
  • "-50% first week" ad — CPA $42. Discount attracts deal hunters, not LinkedIn creators.

The playbook: how to reproduce this on another SaaS

The pattern works beyond Post2Reach. If you're launching a B2B/SMB product where the prospect needs "education" before paying, here's the exact order.

The 7 steps, in order

  1. Find the shared insecurity in your ICP. Something they won't ask anyone ("is my profile any good?", "is my code clean?", "does my landing convert?").
  2. Build a 60-120s self-contained diagnostic that answers that question with a number + an archetype.
  3. Wire in real data — live scraping, API, automated audit. No static quiz. Technical effort signals seriousness.
  4. Film a phone-shot "I tried" UGC — 30-60s, vertical 9:16, natural voiceover. Skip the expensive motion design.
  5. Launch 3 Meta ad angles, keep the winner. Revelation angle, calculator angle, iMessage screenshot angle. Cut at $50 spend if CPA > $10.
  6. Wire in server-side CAPI with fbp + fbc. Without it you pay 3× the rate and Meta optimizes nothing.
  7. Push the result into your product onboarding — not into a PDF email. The moment of highest intent is the second the user sees their score.

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Want us to build this for your product?

Deepthix designs, codes and ships B2B SaaS lead magnets from London. Short cycles (4-6 weeks brief to funnel in prod), fixed fee, CPA guarantee.

[Book a free 30-min audit](https://calendly.com/contact-deepthix/30min) · [email protected]

lead magnet Meta Ads CPA Post2Reach B2B SaaS growth CAPI LinkedIn
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