What it is.
When opens fall and nobody knows why, this tells you whether Gmail is the reason. Postmaster Tools shows the spam rate, reputation, message authentication, plus delivery errors Gmail recorded for a domain you verify.
If you send to a Gmail-heavy list, watch the spam rate dashboard before anything else. Reputation slides before deliverability does, so a domain dropping from high to medium buys you a week or two to sort out list quality while campaigns still land.
What you get.
- The spam rate Gmail users report against your domain, by day.
- A reputation trend you can act on while campaigns are still landing.
- Authentication pass rates measured on mail you sent, which tests the DNS record in practice.
- Delivery error reasons, so a block has a cause you can address.
How to set it up.
Add your sending domain and verify it with the TXT record Google gives you.
Send a normal campaign, then check back in a day, since dashboards need volume before they populate.
Read the spam rate first and treat any sustained rise as a list quality problem before a content problem.
Check the authentication dashboard for SPF, DKIM and DMARC pass rates on the same day's sends.
Add every subdomain you send from as its own entry, because reputation is tracked per domain.
Pricing Plans
Postmaster Tools
$0
one entry per sending domain, verification by TXT record
Use cases
Watch reputation before opens drop
Check the daily spam rate and pause the segment dragging it down.
Authentication proof
Confirm SPF and DKIM pass on mail you have already sent.
Segment forensics
Compare the days you mailed a colder list against the reputation trend.
Best for
Diagnosing a drop in open rates
If Gmail reputation fell in the same week, the problem is deliverability and not your subject lines.
Proving authentication is set up
The pass rates are measured on mail you sent, which is stronger evidence than a DNS record that looks correct.
Watching a new sending domain warm up
Reputation grades over the first weeks tell you whether the ramp is working before volume gets expensive.
Open the tool
Opens on Google in a new tab.