What does my Google Postmaster Score Really Mean?
Understanding Google Postmaster: Why IP Reputation Isn’t the Full Story
Google Postmaster Tools can be helpful for monitoring deliverability, but its IP/domain reputation scores don’t always reflect real email performance. At Numero, we recommend using Postmaster as a diagnostic trend signal, not a standalone grade of email health.
What Postmaster Measures
Postmaster assigns reputation levels based on Gmail’s view of:
- IP and domain/subdomain reputation
- Spam complaint rates
- Authentication (SPF/DKIM/DMARC)
- Delivery errors and security signals
These are useful indicators, but they’re context-dependent and often lag behind actual inbox results.
Why Reputation Can Look Worse Than Performance
A “Bad” Postmaster rating doesn’t automatically mean poor deliverability. Common reasons scores start low or fluctuate:
- New domains/subdomains start cold. Gmail treats new subdomains independently and builds trust from scratch, especially when they’re used primarily for bulk campaign email.
- Dedicated subdomains don’t borrow reputation. Unlike shared ESP domains (used by some competitors), Numero subdomains reflect only that sender’s traffic—so they may look lower early on even with strong performance.
- Volume swings affect scores. Irregular sending or sudden spikes can temporarily depress reputation even if engagement remains healthy.
Engagement Is the Best Measure of Email Health
Mailbox providers care most about how recipients behave. Opens, clicks, replies, and low complaint rates are the strongest proof that your emails are reaching inboxes and resonating.
Healthy Numero performance typically looks like:
- Consistent or improving open rates
- Steady click/CTR trends
- Low spam complaints
- Low bounce and unsubscribe rates
If those are strong, your real-world deliverability is strong — even if Postmaster is slow to show it.
Bottom Line
Use Postmaster for trends, not verdicts.
If engagement is healthy and complaints are low, your email program is in good shape, and your reputation will improve naturally over time with consistent sending.