ZeroBounce vs Postmastery
Side-by-side from the Top 11 ranking of GlockApps vs Validity vs Mail-tester: 11 Best Email Deliverability Tools 2026. Last verified June 15, 2026.
The short answer
ZeroBounce ranks higher on Top 11 (#9 vs #10) for Email marketers and developers improving inbox placement rates. An excellent list verification service with a growing suite of deliverability add-ons.
At a glance
| ZeroBounce | Postmastery | |
|---|---|---|
| Top 11 rank | #9 / GlockApps vs Validity vs Mail-tester: 11 Best Email Deliverability Tools 2026 | #10 / GlockApps vs Validity vs Mail-tester: 11 Best Email Deliverability Tools 2026 |
| Score (out of 9.4) | 7.5 | 7.2 |
| Best for | Verification with add-on tools | Expert consultancy with software |
| Pricing | $ (Pay-as-you-go or $15/mo+) | $$$$ (Custom pricing) |
| HQ | Santa Barbara, USA | Amsterdam, Netherlands |
| Founded | 2015 | 2010 |
ZeroBounce
An excellent list verification service with a growing suite of deliverability add-ons.
www.zerobounce.net/See full entry in GlockApps vs Validity vs Mail-tester: 11 Best Email Deliverability Tools 2026
Postmastery
A specialized consultancy for complex sending infrastructures, supported by their own software.
postmastery.com/See full entry in GlockApps vs Validity vs Mail-tester: 11 Best Email Deliverability Tools 2026
Methodology and scoring weights live at /methodology. No vendor pays for placement — see about.