🧠The Problem
Meet Clara, founder of a B2B SaaS tool helping HR teams streamline onboarding.
Her GTM plan was tight:
- Cold outreach to HR managers
- Inbound via Notion-style landing pages
- Monthly newsletter for waitlist growth
But there was a problem.
"40% of our emails were bouncing. That meant zero replies, spam flags, and a domain on the verge of being torched."
Clara tried:
- Hunter Verify (too expensive for early stage)
- Manual checks (too slow)
- Removing bounced contacts manually (didn't scale)
🛠The Fix
Clara switched to Lero—an API-first email validator built for founders, by founders.
Here's the 3-step process she followed:
1. Validated 3K leads in bulk
- Uploaded CSV to Lero dashboard
- Got results in <1 min
- 972 emails flagged as hard bounces, disposables, or invalid syntax
She filtered and removed those instantly.
2. Integrated live validation on forms
- Connected Lero's real-time API to Webflow & Tally forms
- Blocked bad emails at entry (typos, temp emails, catch-alls)
"We stopped junk emails at the source—without hurting conversions."
3. Retested deliverability score
Using Google Postmaster & Mail-Tester:
- Before: 5.4/10
- After 2 weeks: 9.5/10
- Inbox placement improved across Gmail, Outlook, and Zoho.
📈The Results
| Metric | Before Lero | After Lero |
|---|---|---|
| Bounce rate | 40.2% | 0.97% |
| Open rate (cold emails) | 17.4% | 42.1% |
| Cold reply rate | 0.9% | 5.3% |
| Newsletter growth | 30/wk (avg) | 110/wk (avg) |
| Domain blacklist warnings | 2 in 3 weeks | 0 |
⚡️Why It Worked
Removed junk data
Clara removed bad emails before sending
Filtered fake emails
Lero filtered temporary & typo'd emails
Stopped catch-alls
Her forms stopped letting in bots
Scaled confidently
Gained confidence to scale cold outreach
No contracts
Didn't pay per seat or get locked in
🧪Tools Used (Stack)
| Need | Tool |
|---|---|
| Email validator | Lero ✅ |
| Form builder | Tally + Webflow |
| Outreach | Instantly |
| Deliverability check | Mail-Tester + Postmaster |
| CRM | Notion + Airtable |
Ready to Fix Your Bounce Problem?
You don't need 10 tools, a dev team, or a seed round. You just need clean emails.
💬 Got a question? Ping us on chat—we reply fast (just like our API).
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