● Email reactivation · Placement measured
We run re-engagement campaigns to the customers you already have — and we measure whether those emails actually reach the inbox instead of the spam folder. Most email platforms cannot tell you the difference. Measuring it is the entire job.
30 minutes · No obligation · Your list stays yours
34 of 34 test sends placed in the inbox. Zero in spam.
The measured figure covers Gmail and Yahoo, 17 sends each, across a three-week window. Outlook is carried as a Microsoft baseline and deliberately left out of the number: Microsoft is the hardest inbox in the industry to reach, and folding an easier reading in beside it would flatter the result. Its own placement was clean.
Confirmed by opening each mailbox and looking — spam empty at all three, every send present and findable. Gmail’s Promotions tab counts as inbox, per standard benchmark convention. One Yahoo message was deferred for two and a half hours before landing, which is exactly the kind of throttling a seed panel exists to catch.
This is a record of Heng Dynamics’ own authenticated sending infrastructure, not a client campaign result and not a prediction of yours. We publish the sample size because a percentage without one is worthless.
The gap
When you send a campaign, the receiving mail server either accepts the message or refuses it. Your email platform reports the accepted ones as delivered — and then stops watching. What happens next is invisible to it.
After acceptance, the provider decides where the message goes: the inbox, the promotions tab, the spam folder, or nowhere at all. That decision is made on your domain’s authentication and sending reputation. A campaign can be almost entirely delivered and still be mostly unread, because most of it was filed where nobody looks.
Most platforms report delivery as sends minus bounces. Because bounces on a permission-based list run near 1.5%, that number lands around 98.5% almost regardless of what happened next. Validity, which measures actual placement using seed data rather than acceptance, puts global inbox placement at 87.2% for 2025. The distance between those two figures is the entire reason this service exists. (Validity, 2026 Email Deliverability Benchmark Report.)
The only way to know which side of that line you are on is to send test messages to real monitored mailboxes and look. That is what a seed panel is, and we run one on every campaign.
What your platform reports
Delivered
The receiving server accepted the message. Nothing about where it went afterwards.
What we report
Placed in inbox
Confirmed by test sends to monitored mailboxes at Gmail, Yahoo and Outlook, broken out by provider, on every campaign.
The engagement
We look at two things: your list and your sending setup. How many contacts you hold, how many are still reachable, how many have gone quiet and for how long — and whether your domain is properly authenticated, which is the technical groundwork that decides whether a provider trusts your mail. You get a written read of what is recoverable and what is not, in plain language.
Free · About 30 minutes of your timeBefore anything is sent, the list is verified and the dead addresses removed. Your domain authentication is corrected at the DNS level. The sending infrastructure is warmed so that a sudden burst of mail does not read as an attack. Addresses that would damage your reputation are suppressed rather than mailed. This is the stage nearly every re-engagement campaign skips, and it is the reason nearly every re-engagement campaign underperforms.
A staged sequence goes out to your dormant clients over several weeks — deliberately slowly, because volume spikes are what trigger filtering. Placement is measured on the seed panel throughout, broken out by provider, and reported to you. Your list stays yours, your brand stays yours. We handle sending, monitoring and cleanup.
Where we draw the line
Everything in this business that can honestly be promised is a deliverability outcome. Everything else depends on your offer, your prices and your clients. We will not sell you a number we do not control.
We commit to
We will not promise
Fit
The qualifier was never an industry. It is whether your customers return — and whether anyone on your staff actually owns email deliverability. Almost nobody does, because it is authentication and reputation work rather than marketing, and it sits in the gap between the person who writes the emails and the person who manages the website.
Med spas and aesthetics practices, dental and veterinary clinics, salons and studios, gyms, home services, dealerships, specialty retail — anywhere a second visit is worth as much as the first. If that describes you, the list you have been quietly collecting for years is worth more than you think.
We are a small firm and we work with clients in person wherever that is practical.
The free audit
Bring the number of contacts you hold and the system you keep them in. We will tell you how many are still reachable, whether your domain is set up to be trusted, and what a re-engagement campaign would realistically look like. If the answer is that it is not worth doing, we will say so.
30 minutes · No pitch deck · No obligation