Everything checked so far
Sorting floor
Running now
Nothing running.
Risk flags
Activity
One address, answer now
Quick check
Many addresses, one at a time
Slow mode
Paste a list below. MAILGATE filters locally first, then calls SendGrid at 6 requests per second. Capped at 50,000 addresses.
Large lists, processed in batches
Bulk
Upload a CSV. MAILGATE normalises it, removes duplicates, resolves MX records and drops dead domains before anything reaches SendGrid — every address dropped here is a credit you don't pay for.
Import SendGrid results
SendGrid emails the finished file rather than returning it over the API. Upload that file here to load the verdicts and build statistics.
Processing history
Jobs
Job report
—
What happened to the list
Risk flags
Top domains
Why each verdict
Addresses
Across every job
Statistics
Checks per day
Busiest domains
Worst domains
Highest share undeliverable, minimum 30 addresses
By top-level domain
Look things up, get lists out
Tools
Address history
Search every job for one address — worth doing before paying to validate it again.
Suppression list
Every address that came back undeliverable or risky, one row each. Import this into Sendy as a suppression list so they never receive another campaign.
Storage
Results are kept indefinitely. Deleting a job removes its addresses from the database and from the suppression list.
Connection and behaviour
Settings
SendGrid API key
Needs Email Address Validation Access with the Validation slider set to Full Access.
Processing
How verdicts are decided
| Undeliverable | Bad syntax, no MX or A record, or a disposable domain |
| Risky | A shared address such as admin@, or SendGrid could not confirm the mailbox |
| Deliverable | SendGrid confirmed the address can receive mail |
| Unknown | Passed local checks but SendGrid was never called |