Most inbox load is predictable: notifications, newsletters, receipts. Rules remove it before you see it.
The metrics that matter#
- Authentication pass rate: share of mail passing SPF, DKIM, and DMARC alignment. Healthy: 99% or higher.
- Spam complaint rate: Gmail enforces at 0.3%; stay under 0.1%.
- Hard bounce rate: under 2%; above 5% triggers platform reviews.
- Inbox placement: above 90% across major providers via seed tests.
- Engagement: click and reply rates by segment; opens are unreliable after Mail Privacy Protection.
Where to read them#
- Google Postmaster Tools for Gmail domain reputation, spam rate, and authentication.
- Microsoft SNDS and JMRP for Outlook.com IP reputation and complaints.
- Your ESP's delivery and bounce reports.
- DMARC aggregate reports for authentication by source.
Improving the numbers#
- Create a small set of labels by required action, not topic.
- Auto-archive notifications and route newsletters to a digest.
- Star or flag anything from key contacts or where you are directly addressed.
- Review rules quarterly and delete stale ones.
Frequently asked questions#
Labels or folders: which is better?
Labels allow one message to carry several states. Folders are simpler. Either works if the taxonomy is small.