Gamma uses Customer.io for marketing email and Postmark for transactional/notifications. They rank #3,436 in the Tranco list of most-popular domains. We've also observed sends via Amazon SES. Their email authentication setup is good (score 80/100).
Authentication signals observed in this brand's emails. SPF, DKIM and DMARC are the standard sender-authentication stack — see the DMARC policy below for whether spoofing is actually blocked or just monitored. One-click unsubscribe meets Google & Yahoo's bulk-sender requirements.
SPF / DKIM / DMARC above reflect the last 4 emails we've observed. DMARC policy is read live from DNS.
DMARC reports sent to gamma.app. Policy
p=quarantine means receivers actively block or quarantine spoofed mail.
SPF alignment: all 10 observed emails use a return-path aligned with gamma.app (pm-bounces.gamma.app, bounce.gamma.app, cio72592.gamma.app). SPF authenticates the visible From — supports DMARC directly.
DKIM alignment: all 10 observed emails sign with a domain aligned with gamma.app (gamma.app, cio72592.gamma.app). DKIM authenticates the visible From — supports DMARC directly.
TLS: modern — 80% TLS 1.3 (across 5 sends).
Delivery (last 7 days): 50% under 10 seconds, 0% over 1 minute (across 4 sends).
Brands often use multiple ESPs (e.g. one for marketing, another for transactional/notifications).
Amazon SES 3ESPs we've seen sending email for this brand. Green = confirmed by SPF, sender IP rDNS, or known infra pairing (label shows the source). Grey = observed but not yet confirmed by SPF or PTR.
ESPs this brand has authorized in their SPF record. We confirm them with a green ✓ only after seeing recurring use (3+ emails across 2+ days). Until then they stay here — either we haven't observed any email yet, or we've seen a handful but not enough to call them a regular sender for the brand.
Probed: gamma.app, pm-bounces.gamma.app, cio72592.gamma.app, bounce.gamma.app
Folder distribution across all emails from this brand observed in Gmail inboxes. High inbox % = good deliverability; spam appearances are the headline signal.
| Folder | Count | Share |
|---|---|---|
| inbox | 6 | 60.0% |
| promotions | 4 | 40.0% |
Which ESP's emails are landing where. Sorted by spam % so problem senders surface first. Brands using one ESP for marketing and another for transactional often see very different placement profiles per ESP. Per-ESP folder data only started being captured recently — counts here may be smaller than the total above until backfill catches up.
| ESP | Emails | Placement | Inbox % | Tabs % | Spam % |
|---|---|---|---|---|---|
| Amazon SES | 3 | 100.0% | 0.0% | 0.0% | |
| Customer.io | 1 | 100.0% | 0.0% | 0.0% | |
| Postmark | 6 | 33.3% | 66.7% | 0.0% |
Daily observations per ESP. Brands often run multiple ESPs concurrently — marketing on one, transactional on another — so this chart shows usage rather than switches.
IP addresses gamma.app has been observed sending from, and where their mail landed in Gmail.
| IP | Hostname | Obs | Placement | Reputation |
|---|---|---|---|---|
| 54.240.42.185 | a42-185.smtp-out.amazonses.com |
2 | 2 | Check → |
| 104.245.209.198 | mta198a-ord.mtasv.net |
1 | — | Check → |
| 50.31.205.19 | mta19-ab1.mtasv.net |
1 | — | Check → |
| 50.31.205.29 | mta29-ab1.mtasv.net |
1 | — | Check → |
| 50.31.205.32 | mta32-ab1.mtasv.net |
1 | — | Check → |
| 50.31.205.34 | mta34-ab1.mtasv.net |
1 | — | Check → |
| 104.245.209.210 | mta210a-ord.mtasv.net |
1 | — | Check → |
| 161.38.193.2 | v52.v56f0a4e3.use4.send.mailgun.net |
1 | 1 | Check → |
| 54.240.61.166 | a61-166.smtp-out.us-west-2.amazonses.com |
1 | 1 | Check → |
| Domain | ESPs detected | Delivery (7d) |
|---|---|---|
gamma.app | Postmark 6 Amazon SES 3 Customer.io 1 |
