Email deliverability checker
See why your cold email lands in spam. We live-check your domain's SPF, DKIM & DMARC records and score your email copy — with plain-English fixes. Everything runs in your browser.
1 · Domain authentication
Enter your sending domain (e.g. yourcompany.com). We read your public DNS live — nothing is stored.
2 · Email copy spam score
Paste the subject and body you plan to send. We flag spam triggers before you hit send.
Fixing the records is step one. Landing every time is the job.
AetherMAIL sets up authentication, warms your mailboxes, rotates inboxes, and monitors placement — so your cold email keeps reaching the inbox.
Start free trial14-day free trial · no credit card required
Why your cold email lands in spam
In 2024 Google and Microsoft made SPF, DKIM and DMARC mandatory for anyone sending at volume. If even one is missing or misconfigured, mailbox providers can't trust your domain — and your carefully written outreach never reaches a human. Authentication is the foundation; on top of it sit sender reputation, mailbox warm-up, list quality, and the words in your email. This tool checks the two things you can see instantly: your DNS records and your copy.
What each record does
- SPF — a DNS record listing which servers are allowed to send email for your domain. Missing SPF is an instant trust hit.
- DKIM — a cryptographic signature that proves your email wasn't tampered with in transit. Providers weight it heavily.
- DMARC — tells inbox providers what to do when SPF or DKIM fail (nothing, quarantine, or reject) and where to send reports. Required for bulk senders.
- MX — the records that let your domain receive replies. If you can't receive, your outreach looks one-way and suspicious.
After the records: what actually keeps you in the inbox
Passing all four checks gets you to the starting line — it doesn't win the race. Consistent inbox placement comes from warming new mailboxes gradually, keeping volume human, rotating sending across healthy inboxes, monitoring blacklists and reputation, and pruning bad addresses before you send. That ongoing work is exactly what deliverability software like AetherMAIL automates.
No credit card required · cancel anytime
More free tools: subject line checker · deliverability guide · cold email software
Deliverability checker — questions
What is SPF, DKIM and DMARC?
They're the three email-authentication records mailbox providers check to trust you. SPF lists which servers may send for your domain, DKIM cryptographically signs your mail, and DMARC tells providers what to do if SPF or DKIM fail. Since 2024, Google and Microsoft require all three for bulk senders.
Why do my cold emails land in spam?
Usually missing or misconfigured SPF/DKIM/DMARC, a cold domain that was never warmed up, spam-trigger words or heavy formatting, or poor sender reputation from bounces and complaints. This checker flags the authentication and content issues; warm-up and reputation are handled by a platform like AetherMAIL.
How does the DKIM check work?
DKIM records live at a selector you choose when you set it up, so there's no universal location. We probe the most common selectors (Google, Microsoft, SendGrid, Mailgun, and others). If your provider uses a custom selector we may not detect it automatically — that doesn't mean DKIM is missing.
Is this tool really free and private?
Yes. The DNS lookups run live in your browser against public records; the copy analysis runs entirely on your device. No signup, and nothing you type is stored or sent to a server.