Deliverability Setup Checker by lemlist Review
Introduction
You’ve crafted the perfect cold email. Your subject line converts. Your CTA is irresistible. Yet replies are low — and worse, messages vanish into spam.
The culprit? Poor email deliverability hygiene — and it almost always starts with your technical setup, not your copy.
lemlist’s Deliverability Setup Checker is a battle-tested, no-cost diagnostic tool that scans your domain’s core authentication records in seconds — revealing hidden issues before they sink your campaigns. In this hands-on review, we test its accuracy, depth, and actionable feedback for founders, marketers, and sales ops teams.
What Is the Deliverability Setup Checker?
As confirmed on lemlist’s official page, this is five tools in one — a unified scanner for the foundational pillars of email deliverability:
- ✅ SPF Checker — Validates Sender Policy Framework records
- ✅ DKIM Checker — Confirms DomainKeys Identified Mail setup
- ✅ DMARC Checker — Verifies policy enforcement (none/quarantine/reject)
- ✅ MX Checker — Ensures incoming mail routing is functional
- ✅ Blacklist Checker — Scans 10+ major DNSBLs (e.g., Spamhaus, Barracuda)
Unlike generic DNS lookup tools, it interprets results in context — telling you not just what’s wrong, but why it matters and how it impacts inbox placement.
Key Features
- ✅ 100% Free — No Signup or Limits — Scan any domain instantly
- ✅ All-in-One Dashboard — Single interface for 5 critical checks
- ✅ Plain-English Explanations — No jargon; clear “pass/fail + impact” labels
- ✅ Blacklist Monitoring — Detects listings that silently kill deliverability
- ✅ Mobile-Responsive UI — Works on desktop and tablet
Note: It does not validate custom tracking domains (CTD) — that requires a lemlist subscription — but covers everything else needed for baseline inbox safety.
How to Use It (Step-by-Step)
- Visit https://www.lemlist.com/free-tools/deliverability-setup-checker
- Enter your domain (e.g., yourcompany.com)
- Click “Check domain setup”
- Wait 5–10 seconds — full report loads
- Review each section:
- 🔵 Pass = green ✅
- 🔴 Fail/Missing = red ❌ + explanation
- Act on recommendations (e.g., fix SPF syntax, add DMARC record)
💡 Pro Tip: Run this before launching any cold email campaign — and re-check monthly. Even small DNS drifts can trigger spam filters over time.
Use Cases / Who Should Use This Tool
- 🚀 Founders validating domain setup before first outreach
- 📩 Cold emailers troubleshooting low reply rates
- 🛠️ Sales ops auditing team sending domains
- 🎯 Agencies onboarding new client domains
- 🧪 Growth teams A/B testing domain configurations
Critical for anyone using Gmail Workspace, Outlook, or ESPs (e.g., lemlist, Mailgun, SendGrid) for outbound.
Pros and Cons
✅ Pros | ❌ Cons |
✔️ Instant, holistic domain health snapshot | ✖️ No CTD (custom tracking domain) validation in free tier |
✔️ Explains why each record matters (not just pass/fail) | ✖️ No historical tracking or alerts |
✔️ Blacklist scan saves hours of manual checks | ✖️ No auto-fix or DNS record generator (links to separate tools) |
✔️ Zero friction — no email, no signup | ✖️ No API for automated monitoring |
Is It Free?
Yes — 100% free, with no usage limits. All core deliverability checks are available without account creation.
Alternatives
- MXToolbox — robust but fragmented (separate tools per check)
- Google Admin Toolbox — SPF/DKIM only; no DMARC or blacklist
- Mail-Tester.com — email-based scan (requires sending test email)
lemlist’s tool wins for integration, clarity, and actionability — especially for non-technical users.
Final Verdict
⭐ 4.9 / 5 — A must-run diagnostic for every outbound sender. By bundling SPF, DKIM, DMARC, MX, and blacklist checks into one intuitive interface — with plain-language impact explanations — it turns a complex, high-stakes process into a 30-second habit. For solopreneurs and teams serious about protecting sender reputation, this is non-negotiable pre-launch hygiene.
Highly recommended as step zero in any cold email workflow.
FAQ
Q1: Does it work with subdomains (e.g., mail.yourcompany.com)?
A: Yes — enter the full subdomain. SPF/DKIM/DMARC must be configured at that level.
Q2: How often should I run this check?
A: Before every new campaign, after DNS changes, and at least monthly for active domains.
Q3: What if my domain fails DMARC but passes SPF/DKIM?
A: That’s common. DMARC requires either SPF or DKIM alignment — but a missing DMARC record means you forfeit control over how receivers handle failures. Add a DMARC policy (start with p=none) to monitor first.
Q4: Can it fix issues automatically?
A: No — but lemlist offers free companion tools: