Free, first-party, and most senders never open it. Your Gmail domain reputation, straight from Google's mouth.
Google Postmaster Tools is a deliverability tool: placement testing and monitoring so problems surface before they cost a month. It earned its place in the GrowthPal tool directory, where every entry is written from the operator's side of the desk: clearly marked partnerships and one practical take per tool.
Where it fits: as the smoke detector. Run placement checks before scaling, after any dip, and on a schedule in between.
Visit Google Postmaster Tools ↗Listed on merit. GrowthPal has no commercial relationship with Google Postmaster Tools unless the badge above says Partner, and either way the words are ours. Vendors: corrections welcome via the contact page.
We build and run the whole machine, Google Postmaster Tools-class tooling included, and test 10 to 15 angles until your market answers. Start free.