How does an Inbox Placement Test work?

Our Inbox Placement Test evaluates the three pillars used by Gmail, Microsoft 365 (Outlook), and Yahoo filters in 2026: (1) Sender Domain Authentication & DNSBL Reputation (SPF, DMARC, MX, rDNS), (2) Subject & Body Spam Trigger Density, and (3) Recipient List Hygiene (<1% hard bounce threshold).

What is the #1 reason emails land in the Spam folder instead of the Primary Inbox?

Sending to unverified email lists with a hard bounce rate above 1.5%–2% or missing DMARC authentication immediately degrades your domain reputation with Google Postmaster Tools and Microsoft SmartScreen, routing subsequent emails to Spam.

2026 GMAIL, OUTLOOK & YAHOO INBOX PLACEMENT TESTER

Free Inbox Placement Test & Spam Filter Predictor

Q: What is the #1 reason emails land in the Spam folder instead of the Primary Inbox?

Sending to unverified email lists with a hard bounce rate above 1.5%–2% or missing DMARC authentication immediately degrades your domain reputation with Google Postmaster Tools and Microsoft SmartScreen, routing subsequent emails to Spam.

Will your campaign land in the Primary Inbox, Promotions Tab, or Spam Folder? Test your sending domain's live DNS authentication + email copy below, and verify your recipient list so hard bounces never tank your sender reputation.

Step 1: Test Your Sender Domain + Email Content

Sending Domain (or From Email)

Email Subject Line

Email Body Copy

Drop Your CSV, TXT or Multi-Sheet Excel (.XLSX) List

Instant client-side pre-scan (0 credits) + live 5-email Smart SMTP sample check before you even sign up.

Native .CSV, .TXT, .XLS & Multi-Sheet .XLSX Zero-Retention RAM Processing $0 for Unknowns & Duplicates From $19 (5,000 Credits · Never Expire)